StatementExpressions.dfy(55,11): Error: cannot prove termination; try supplying a decreases clause
Execution trace:
    (0,0): anon0
    (0,0): anon6_Then
    (0,0): anon8_Then
StatementExpressions.dfy(59,13): Error: assertion violation
Execution trace:
    (0,0): anon0
    (0,0): anon6_Then
    StatementExpressions.dfy(53,7): anon8_Else
StatementExpressions.dfy(77,5): Error: possible division by zero
Execution trace:
    (0,0): anon0
    (0,0): anon4_Else
StatementExpressions.dfy(88,4): Error: value assigned to a nat must be non-negative
Execution trace:
    (0,0): anon0
    (0,0): anon4_Else
StatementExpressions.dfy(98,17): Error: cannot prove termination; try supplying a decreases clause
Execution trace:
    (0,0): anon0
    (0,0): anon6_Then

Dafny program verifier finished with 17 verified, 5 errors