REVIEW 3 major objections 7 minor 42 references
SSH-Net: A Self-Supervised and Hybrid Network for Noisy Image Watermark Removal
T0 review · 3 major / 7 minor · reviewed 2026-08-15 · deepseek-v4-flash
Pith's one-line read Watermark removal can be learned from the watermarked image alone, without paired clean examples, by treating randomly re-watermarked copies as the training target.
desk verdict Plausible architecture, extensive experiments, but the self-supervised target construction contradicts the paper's own blend equation; the PSNR gains are unexplained. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The load-bearing object is the synthesized target $Y_w$, formed by re-watermarking the input $X_w$, together with the asserted identity $\mathbb{E}\{Y_w|X_w\}=Y$ that converts it into a usable training signal. The architecture's second engine is the Sparse Transformer U-Net, whose top-$k$ sparse self-attention retains only the largest entries of the transposed attention map so that localized watermark patterns can be captured without quadratic spatial cost. The shared encoder and gate mechanism then coordinate the two decoders: the gate uses the watermark-removal features to modulate and damp the denoising features before fusion.
What would settle it
Take one watermarked image $X_w$ whose clean original $Y$ and watermark $W$ are known; generate many random targets $Y_w$ by the paper's recipe and average them. If the average is not $Y$ but instead equals $\alpha W+(1-\alpha)X_w$ averaged, differing from $Y$ whenever the watermark mean is nonzero, the unbiasedness claim is disproved. A second check is to train SSH-Net on synthetic paired data where $Y$ is known and compare its predictions against a model trained directly on the true $Y$ targets.
Extended reading notes
Core claim
The central claim is that the self-supervised objective in Eq. (4), which minimizes loss between the network output and a synthesized, still-watermarked target $Y_w$, converges to the same solution as supervised training against the true clean image $Y$. The paper argues from the composition model $X_w(p)=\alpha(p)W(p)+(1-\alpha(p))Y(p)$ that randomly adding extra watermarks to $X_w$ produces targets drawn from the same corruption distribution, giving $\mathbb{E}\{Y_w|X_w\}=Y$; this unbiasedness is what lets the synthesized targets stand in for ground truth. Around that idea, SSH-Net decomposes the task into a lightweight CNN noise-removal decoder, a Transformer-based decoder that removes watermarks and noise together using sparse self-attention, a shared encoder, and a gated feature-fusion unit, and reports that this design beats previous self-supervised and supervised baselines on PSNR, SSIM, and LPIPS at several noise levels and watermark opacities.
Load-bearing premise
The load-bearing premise is that a target made by randomly adding more watermarks to the already-watermarked input is, on average, exactly the clean image; if that expectation is wrong, the whole self-supervised training signal is wrong.
Editorial extensions
If this is right
- Training watermark-removal models no longer requires paired clean images; any watermarked collection, including images scraped from the web, can supply its own training targets.
- The dual-task split means the simpler denoising path can be made lightweight while the harder watermark path carries the transformer cost, a design choice that transfers to other degradation pairs.
- Because the sparse attention keeps only top-$k$ attention entries, computation stays low for high-resolution inputs, making the approach more practical for real deployment.
- The reported results imply that a single model can handle blind transparency and blind noise ranges simultaneously, removing the need to know the watermark strength or noise level at test time.
Reading between the lines
- If the unbiasedness equality fails for real watermarks, which typically have nonzero mean and spatially structured transmittance, the method likely learns a watermark-to-watermark mapping rather than true removal; a direct check would compare predictions against known ground truth on synthetic data.
- The same re-corrupt-the-input target recipe could be tried on other structured artifacts with a known blend model, such as subtitles, timestamps, logos, or semi-transparent overlays, where supervised pairs are equally scarce.
- The gating behavior the paper visualizes could be turned into a per-pixel confidence map that flags where the model is uncertain, potentially useful for downstream tasks like detecting whether a watermark was present.
- The top-$k$ sparsity choice assumes watermark attention is localized; measuring whether attention actually concentrates inside watermark regions would tell whether the inductive bias matches watermark structure.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes SSH-Net, a self-supervised hybrid network for removing both visible watermarks and Gaussian noise from images. The claimed novelty is a training scheme that synthesizes a reference watermark-free image Y_w by randomly adding additional watermarks to the already-watermarked image X_w; Sec. 3.1 asserts that this construction makes Y_w an unbiased estimator of the clean image Y, i.e., E[Y_w|X_w] = Y, enabling the empirical risk objective in Eq. (4) to be trained without paired clean data. Architecturally, the method combines a shared CNN encoder, a lightweight CNN denoising decoder (NRD), a Transformer-based watermark-and-noise decoder (WNRD) with sparse self-attention, and a gated feature fusion unit. Experiments on PASCAL VOC benchmarks across multiple noise levels and watermark transparencies report consistent improvements over PSLNet and other baselines, and ablations show the contribution of each architectural component.
Significance. If the self-supervised target construction were valid, the paper would make a useful contribution: the hybrid dual-decoder design, sparse attention, and the broad benchmark comparison are sensible and potentially impactful for practical watermark removal without paired data. However, the central statistical claim is internally inconsistent with the paper's own equations, and the empirical gains are not explained by the described training protocol. The manuscript also provides no code, no error bars, and no machine-checked proofs, so the strength of the empirical claims cannot be independently assessed. The significance rests entirely on the unbiasedness assertion, which fails, and therefore the contribution, as currently stated, cannot be credited.
major comments (3)
- [Sec. 3.1, Eqs. (1)-(4)]
- [Sec. 3.5, Eqs. (17)-(21)]
- [Sec. 4.4, Table 10]
minor comments (7)
- [Sec. 1] There is a duplicated sentence fragment: 'by learning directly from the corrupted image itself. by learning directly from the corrupted image itself.' should be reduced to one occurrence.
- [Sec. 3.3] The word 'nstead' should be 'Instead' in the sentence describing the NAFBlock.
- [Sec. 3.4] The module name 'WNRN' appears in the text and should be 'WNRD' for consistency with the rest of the paper.
- [Figure 1 caption] The caption contains the typo 'groud-truth'; it should be 'ground-truth'.
- [Eq. (15)] The notation 'top-k (row j)' is unclear because the attention map M has dimensions d_l × d_l and the softmax is applied over one dimension; please specify the exact axis along which the top-k selection is performed and whether the mask is applied before or after the softmax.
- [Sec. 3.2 and Eq. (19)] The output of the watermark-and-noise decoder is denoted Y_wn in Sec. 3.2 but Y_wm in Eq. (19); please use a single consistent notation.
- [Sec. 4.1] The test-set description says 21 PASCAL VOC images are processed with a random watermark and a fixed noise level, yet the total is stated as 252 test images per scenario; the arithmetic (21 × 4 × 3 = 252) is not explained and should be clarified.
Circularity Check
Sec. 3.1 asserts E{Y_w|X_w}=Y for a target obtained by re-watermarking X_w, yet the paper's own blend equation makes E{Y_w|X_w} a re-watermarked input; the central self-supervised derivation is circular.
-
self definitional
[Sec. 3.1, Eqs. (1), (3), (4); target synthesis; losses in Sec. 3.5, Eqs. (18)-(21)]
"Specifically, the synthesized reference image Y_w is generated by randomly adding additional watermarks into the watermarked image X_w. This ensures that both the input image and the synthesized output image are drawn from the same watermark corruption distribution, approximating the condition E{Y_w|X_w} = Y. In other words, Y_w serves as an unbiased estimator of the clean image Y, conditional on the watermarked image X_w."
Under Eq. (1), X_w = αW + (1−α)Y. If Y_w is another watermark blended into X_w, Y_w = βW′ + (1−β)X_w, so E[Y_w|X_w] = βE[W′] + (1−β)X_w, a re-watermarked input, not Y. The asserted unbiasedness would require X_w to already be the clean image up to an affine map, i.e., exactly the inversion to be learned. Thus moving from Eq. (3) to Eq. (4) assumes the conclusion: Y_w is defined from X_w and then declared to represent Y on average. For the L2 loss in Eq. (4), the minimizer is E[Y_w|X_w] ≈ X_w, so the protocol trains toward a doubly watermarked image; reported clean-image gains do not follow from the stated derivation.
full rationale
The central self-supervised claim collapses at the construction of Y_w. The paper defines the synthetic reference by randomly adding further watermarks to X_w and then asserts E{Y_w|X_w}=Y. By the paper's own blend model (Eq. (1)), that conditional expectation is a re-watermarked version of the input rather than the clean image; the unbiasedness condition is not derived but is exactly the property to be established. All subsequent losses (Eqs. (18)-(21)) compare outputs against Y_w, so the same circular target propagates through every supervision term. This is not a self-citation or uniqueness-import problem: PSLNet and Noise2Noise are external prior work, and the architecture ablations are empirically self-contained. The flaw is self-definitional: the 'synthesized reference watermark-free image' is, by construction, a doubly watermarked image, so Eq. (4) trains toward the input's watermarked version. The stark sigma=0 result (49.38 dB) would require an undocumented target-generation protocol or clean-image supervision; it cannot be derived from the stated unbiasedness argument. Score 8 reflects that the paper's headline claim reduces by definition to a target that is not the clean image.
Assumptions & free parameters
free parameters (6)
- loss weight alpha =
0.024
- top-k rates for sparse attention =
(1/2, 2/3, 3/4, 4/5)
- per-level block counts (L1-L5) =
(2,4,4,6,6)
- number of attention heads =
(4,8,8,8,4)
- FFN expansion ratio =
2.66
- channel width =
48
assumptions (4)
- ad hoc to paper The synthesized target Y_w is an unbiased estimator of the clean image Y: E{Y_w|X_w}=Y
- domain assumption Additive Gaussian noise K is zero-mean and independent of image content
- domain assumption Watermark blend model X_w(p) = alpha(p)W(p)+(1-alpha(p))Y(p) holds
- ad hoc to paper Minimizing a mixed L1 and perceptual loss against an unbiased target recovers the clean image
Cite this review
Pith. "Pith review of SSH-Net: A Self-Supervised and Hybrid Network for Noisy Image Watermark Removal." pith.science (2026). https://pith.science/paper/GEJJN7D6
@misc{pith2026250505088,
author = {Pith},
title = {Pith review of: SSH-Net: A Self-Supervised and Hybrid Network for Noisy Image Watermark Removal},
year = {2026},
howpublished = {\url{https://pith.science/paper/GEJJN7D6}},
note = {Machine review of arXiv:2505.05088}
}
read the original abstract
Visible watermark removal is challenging due to its inherent complexities and the noise carried within images. Existing methods primarily rely on supervised learning approaches that require paired datasets of watermarked and watermark-free images, which are often impractical to obtain in real-world scenarios. To address this challenge, we propose SSH-Net, a Self-Supervised and Hybrid Network specifically designed for noisy image watermark removal. SSH-Net synthesizes reference watermark-free images using the watermark distribution in a self-supervised manner and adopts a dual-network design to address the task. The upper network, focused on the simpler task of noise removal, employs a lightweight CNN-based architecture, while the lower network, designed to handle the more complex task of simultaneously removing watermarks and noise, incorporates Transformer blocks to model long-range dependencies and capture intricate image features. To enhance the model's effectiveness, a shared CNN-based feature encoder is introduced before dual networks to extract common features that both networks can leverage. Our code will be available at https://github.com/wenyang001/SSH-Net.
Figures
Figures from the paper (2 more)
Reference graph
Works this paper leans on
-
[1]
Protecting publicly-available images with an invisible image watermark
Gordon W Braudaway. Protecting publicly-available images with an invisible image watermark. In Proceedings of international conference on image processing, volume 1, pages 524--527. IEEE, 1997
work page 1997
-
[2]
Tsrformer: Transformer based two-stage refinement for single image shadow removal
Hua-En Chang, Chia-Hsuan Hsieh, Hao-Hsiang Yang, I Chen, Yi-Chung Chen, Yuan-Chun Chiang, Zhi-Kai Huang, Wei-Ting Chen, Sy-Yen Kuo, et al. Tsrformer: Transformer based two-stage refinement for single image shadow removal. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 1436--1446, 2023
work page 2023
-
[3]
Simple baselines for image restoration
Liangyu Chen, Xiaojie Chu, Xiangyu Zhang, and Jian Sun. Simple baselines for image restoration. In European conference on computer vision, pages 17--33. Springer, 2022
work page 2022
-
[4]
Learning a sparse transformer network for effective image deraining
Xiang Chen, Hao Li, Mingqiang Li, and Jinshan Pan. Learning a sparse transformer network for effective image deraining. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 5896--5905, 2023
work page 2023
-
[5]
Leveraging unlabeled data for watermark removal of deep neural networks
Xinyun Chen, Wenxiao Wang, Yiming Ding, Chris Bender, Ruoxi Jia, Bo Li, and Dawn Song. Leveraging unlabeled data for watermark removal of deep neural networks. In ICML workshop on Security and Privacy of Machine Learning, pages 1--6, 2019
work page 2019
-
[6]
Large-scale visible watermark detection and removal with deep convolutional networks
Danni Cheng, Xiang Li, Wei-Hong Li, Chan Lu, Fake Li, Hua Zhao, and Wei-Shi Zheng. Large-scale visible watermark detection and removal with deep convolutional networks. In Pattern Recognition and Computer Vision: First Chinese Conference, PRCV 2018, Guangzhou, China, November 23-26, 2018, Proceedings, Part III 1, pages 27--40. Springer, 2018
work page 2018
-
[7]
On the effectiveness of visible watermarks
Tali Dekel, Michael Rubinstein, Ce Liu, and William T Freeman. On the effectiveness of visible watermarks. In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, pages 2146--2154, 2017
work page 2017
-
[8]
DRD-Net: Detail-recovery Image Deraining via Context Aggregation Networks
Sen Deng, Mingqiang Wei, Jun Wang, Luming Liang, Haoran Xie, and Meng Wang. Drd-net: Detail-recovery image deraining via context aggregation networks. arXiv preprint arXiv:1908.10267, 2019
work page Pith review arXiv 1908
Show all 42 references
-
[9]
An image is worth 16x16 words: Transformers for image recognition at scale
Alexey Dosovitskiy. An image is worth 16x16 words: Transformers for image recognition at scale. arXiv preprint arXiv:2010.11929, 2020
2010 arXiv
-
[10]
The pascal visual object classes challenge: A retrospective
Mark Everingham, SM Ali Eslami, Luc Van Gool, Christopher KI Williams, John Winn, and Andrew Zisserman. The pascal visual object classes challenge: A retrospective. International journal of computer vision, 111: 0 98--136, 2015
2015
-
[11]
Real-time attacks on robust watermarking tools in the wild by cnn
Linfeng Geng, Weiming Zhang, Haozhe Chen, Han Fang, and Nenghai Yu. Real-time attacks on robust watermarking tools in the wild by cnn. Journal of Real-Time Image Processing, 17: 0 631--641, 2020
2020
-
[12]
Image quality metrics: Psnr vs
Alain Hore and Djemel Ziou. Image quality metrics: Psnr vs. ssim. In 2010 20th international conference on pattern recognition, pages 2366--2369. IEEE, 2010
2010
-
[13]
New watermark-removal method based on eigen-image energy
T-C Hsu, W-S Hsieh, John Y Chiang, and T-S Su. New watermark-removal method based on eigen-image energy. IET Information Security, 5 0 (1): 0 43--50, 2011
2011
-
[14]
An algorithm for removable visible watermarking
Yongjian Hu, Sam Kwong, and Jiwu Huang. An algorithm for removable visible watermarking. IEEE Transactions on Circuits and Systems for Video Technology, 16 0 (1): 0 129--133, 2005
2005
-
[15]
Attacking visible watermarking schemes
Chun-Hsiang Huang and Ja-Ling Wu. Attacking visible watermarking schemes. IEEE transactions on multimedia, 6 0 (1): 0 16--30, 2004
2004
-
[16]
Noise2void-learning denoising from single noisy images
Alexander Krull, Tim-Oliver Buchholz, and Florian Jug. Noise2void-learning denoising from single noisy images. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 2129--2137, 2019
2019
-
[17]
Noise2noise: Learning image restoration without clean data
Jaakko Lehtinen, Jacob Munkberg, Jon Hasselgren, Samuli Laine, Tero Karras, Miika Aittala, and Timo Aila. Noise2noise: Learning image restoration without clean data. In International Conference on Machine Learning, pages 2965--2974. PMLR, 2018
2018
-
[18]
Towards photo-realistic visible watermark removal with conditional generative adversarial networks
Xiang Li, Chan Lu, Danni Cheng, Wei-Hong Li, Mei Cao, Bo Liu, Jiechao Ma, and Wei-Shi Zheng. Towards photo-realistic visible watermark removal with conditional generative adversarial networks. In Image and Graphics: 10th International Conference, ICIG 2019, Beijing, China, Aug...
2019
-
[19]
Swinir: Image restoration using swin transformer
Jingyun Liang, Jiezhang Cao, Guolei Sun, Kai Zhang, Luc Van Gool, and Radu Timofte. Swinir: Image restoration using swin transformer. In Proceedings of the IEEE/CVF international conference on computer vision, pages 1833--1844, 2021
2021
-
[20]
Self-supervised learning and adaptation for single image dehazing
Yudong Liang, Bin Wang, Wangmeng Zuo, Jiaying Liu, and Wenqi Ren. Self-supervised learning and adaptation for single image dehazing. In IJCAI, pages 1137--1143, 2022
2022
-
[21]
Bitstream-corrupted jpeg images are restorable: Two-stage compensation and alignment framework for image restoration
Wenyang Liu, Yi Wang, Kim-Hui Yap, and Lap-Pui Chau. Bitstream-corrupted jpeg images are restorable: Two-stage compensation and alignment framework for image restoration. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 9979--9988, 2023
2023
-
[22]
Bytenet: Rethinking multimedia file fragment classification through visual perspectives
Wenyang Liu, Kejun Wu, Tianyi Liu, Yi Wang, Kim-Hui Yap, and Lap-Pui Chau. Bytenet: Rethinking multimedia file fragment classification through visual perspectives. IEEE Transactions on Multimedia, pages 1--14, 2024. doi:10.1109/TMM.2024.3521830
2024
-
[23]
Swin transformer: Hierarchical vision transformer using shifted windows
Ze Liu, Yutong Lin, Yue Cao, Han Hu, Yixuan Wei, Zheng Zhang, Stephen Lin, and Baining Guo. Swin transformer: Hierarchical vision transformer using shifted windows. In Proceedings of the IEEE/CVF international conference on computer vision, pages 10012--10022, 2021
2021
-
[24]
A novel image recovery algorithm for visible watermarked images
Soo-Chang Pei and Yi-Chong Zeng. A novel image recovery algorithm for visible watermarked images. IEEE Transactions on information forensics and security, 1 0 (4): 0 543--550, 2006
2006
-
[25]
A survey of digital watermarking techniques, applications and attacks
Prabhishek Singh and Ramneet Singh Chadha. A survey of digital watermarking techniques, applications and attacks. International Journal of Engineering and Innovative Technology (IJEIT), 2 0 (9): 0 165--175, 2013
2013
-
[26]
Vision transformers for single image dehazing
Yuda Song, Zhuqing He, Hui Qian, and Xin Du. Vision transformers for single image dehazing. IEEE Transactions on Image Processing, 32: 0 1927--1941, 2023
1927
-
[27]
A self-supervised network for image denoising and watermark removal
Chunwei Tian, Jingyu Xiao, Bob Zhang, Wangmeng Zuo, Yudong Zhang, and Chia-Wen Lin. A self-supervised network for image denoising and watermark removal. Neural Networks, 174: 0 106218, 2024 a
2024
-
[28]
Perceptive self-supervised learning network for noisy image watermark removal
Chunwei Tian, Menghua Zheng, Bo Li, Yanning Zhang, Shichao Zhang, and David Zhang. Perceptive self-supervised learning network for noisy image watermark removal. IEEE Transactions on Circuits and Systems for Video Technology, 2024 b
2024
-
[29]
Transweather: Transformer-based restoration of images degraded by adverse weather conditions
Jeya Maria Jose Valanarasu, Rajeev Yasarla, and Vishal M Patel. Transweather: Transformer-based restoration of images degraded by adverse weather conditions. In Proceedings of the IEEE/CVF Conference on Computer Vision and Pattern Recognition, pages 2353--2363, 2022
2022
-
[30]
Crformer: A cross-region transformer for shadow removal
Jin Wan, Hui Yin, Zhenyao Wu, Xinyi Wu, Zhihao Liu, and Song Wang. Crformer: A cross-region transformer for shadow removal. Image and Vision Computing, 151: 0 105273, 2024
2024
-
[31]
Fastderainnet: A deep learning algorithm for single image deraining
Xiuwen Wang, Zhiwei Li, Hongtao Shan, Zhiyuan Tian, Yuanhong Ren, and Wuneng Zhou. Fastderainnet: A deep learning algorithm for single image deraining. IEEE Access, 8: 0 127622--127630, 2020
2020
-
[32]
Image quality assessment: from error visibility to structural similarity
Zhou Wang, Alan C Bovik, Hamid R Sheikh, and Eero P Simoncelli. Image quality assessment: from error visibility to structural similarity. IEEE transactions on image processing, 13 0 (4): 0 600--612, 2004
2004
-
[33]
Image de-raining transformer
Jie Xiao, Xueyang Fu, Aiping Liu, Feng Wu, and Zheng-Jun Zha. Image de-raining transformer. IEEE Transactions on Pattern Analysis and Machine Intelligence, 45 0 (11): 0 12978--12995, 2022
2022
-
[34]
An automatic visible watermark removal technique using image inpainting algorithms
Chaoran Xu, Yao Lu, and Yuanpin Zhou. An automatic visible watermark removal technique using image inpainting algorithms. In 2017 4th International Conference on Systems and Informatics (ICSAI), pages 1152--1157. IEEE, 2017
2017
-
[35]
Metaformer is actually what you need for vision
Weihao Yu, Mi Luo, Pan Zhou, Chenyang Si, Yichen Zhou, Xinchao Wang, Jiashi Feng, and Shuicheng Yan. Metaformer is actually what you need for vision. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 10819--10829, 2022
2022
-
[36]
Restormer: Efficient transformer for high-resolution image restoration
Syed Waqas Zamir, Aditya Arora, Salman Khan, Munawar Hayat, Fahad Shahbaz Khan, and Ming-Hsuan Yang. Restormer: Efficient transformer for high-resolution image restoration. In Proceedings of the IEEE/CVF conference on computer vision and pattern recognition, pages 5728--5739, 2022
2022
-
[37]
Beyond a gaussian denoiser: Residual learning of deep cnn for image denoising
Kai Zhang, Wangmeng Zuo, Yunjin Chen, Deyu Meng, and Lei Zhang. Beyond a gaussian denoiser: Residual learning of deep cnn for image denoising. IEEE transactions on image processing, 26 0 (7): 0 3142--3155, 2017 a
2017
-
[38]
Learning deep cnn denoiser prior for image restoration
Kai Zhang, Wangmeng Zuo, Shuhang Gu, and Lei Zhang. Learning deep cnn denoiser prior for image restoration. In Proceedings of the IEEE conference on computer vision and pattern recognition, pages 3929--3938, 2017 b
2017
-
[39]
Ffdnet: Toward a fast and flexible solution for cnn-based image denoising
Kai Zhang, Wangmeng Zuo, and Lei Zhang. Ffdnet: Toward a fast and flexible solution for cnn-based image denoising. IEEE Transactions on Image Processing, 27 0 (9): 0 4608--4622, 2018 a
2018
-
[40]
The unreasonable effectiveness of deep features as a perceptual metric
Richard Zhang, Phillip Isola, Alexei A Efros, Eli Shechtman, and Oliver Wang. The unreasonable effectiveness of deep features as a perceptual metric. In CVPR, 2018 b
2018
-
[41]
Object detection with deep learning: A review
Zhong-Qiu Zhao, Peng Zheng, Shou-tao Xu, and Xindong Wu. Object detection with deep learning: A review. IEEE transactions on neural networks and learning systems, 30 0 (11): 0 3212--3232, 2019
2019
-
[42]
write newline
" write newline "" before.all 'output.state := FUNCTION n.dashify 't := "" t empty not t #1 #1 substring "-" = t #1 #2 substring "--" = not "--" * t #2 global.max substring 't := t #1 #1 substring "-" = "-" * t #2 global.max substring 't := while if t #1 #1 substring * t #2 gl...
Reviewed August 15, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.