Thank you for the suggestion.
I think this happens to be correct because c has value 1 at c[0,1], and a==b returns True at position [0,1].
If they all have, say value 3 at the position [0,1] then this will not work.
What’s more important is I may also want to compare among more than 3 tensors, like choosing equal elements in 5 tensors. In that case, judging one by one may seem too wordy and inefficient.