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[Assignment #5] Loop invariant init #385

Closed ph1025 closed 1 month ago

ph1025 commented 1 month ago

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    let low = ref 0 in
    let high = ref (length a) in
    while !low < !high do
      invariant { 0 <= !low < !high <= length a && 0<length a}...

I execute this code and for loop invariant initialize test, I get "0<length a" works, but "!low < !high" has questioned. I just substituted a variable but why I don't know why "!low < !high" has questioned. Can I get some advice? Thank you.

Jaewookim08 commented 1 month ago

I believe there's a mistake. I tested your code, and 0 < length's loop invariant init is not verified (nor should it be).