git-issue-664.dfy(13,18): Error: possible division by zero
git-issue-664.dfy(15,9): Error: possible division by zero
git-issue-664.dfy(17,18): Error: possible division by zero
git-issue-664.dfy(19,18): Error: possible division by zero

Dafny program verifier finished with 0 verified, 4 errors
