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This commit is contained in:
Janggun Lee
2024-07-30 15:26:33 +09:00
parent d34f586e4d
commit af889722bc
64 changed files with 452 additions and 384 deletions
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9
assets/why3/assignment05/max.mlw
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@@ -2,11 +2,11 @@
Given an array `a` of integers with length `n` greater than `0`,
return `max_idx`, the index of the maximum element of that array.
E.g. `max_idx [5, 12, 34, 10] 4` will return `2`
E.g. `max_idx [4, 3, 2] 3` will return `0`
E.g. `max_idx [1, 2, 3, 4] 4` will return `3`
Prove the below program indeed follows the given specification,
by giving an appropriate invariant.
*)
@@ -22,12 +22,13 @@ module Max
requires { n = length a }
ensures { 0 <= max_idx <= n-1 }
ensures { forall i. 0 <= i <= n-1 -> a[i] <= a[max_idx] }
=
=
let ref max_idx = 0 in
for i = 0 to n-1 do
invariant { 0 <= max_idx <= n-1 }
(* IMPORTANT: DON'T MODIFY THE ABOVE LINES *)
invariant { true (* TODO: Replace `true` with your solution. Your solution MUST be a single line, at line number 30. DON'T add another line of codes. *) }
(* TODO: Replace `true` with your solution. Your solution MUST be a single line, at line 31. DON'T add more code above or below. *)
invariant { true }
(* IMPORTANT: DON'T MODIFY THE BELOW LINES *)
if a[max_idx] < a[i] then max_idx <- i;
done;