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const N: int;
axiom 0 <= N;
procedure P(K: int)
requires 0 <= K;
{
var b: bool, x, k: int;
if (!b) {
b := !b;
}
x := if b then 13 else 10;
k := K;
while (k != 0) {
x := x + k;
k := k - 1;
}
assert 13 <= x;
}
procedure Thresholds0()
{
var i: int;
i := 0;
while (i < 200)
{
i := i + 1;
}
assert i == 200;
}
procedure Thresholds1()
{
var i: int;
i := 0;
while (i <= 199)
{
i := i + 1;
}
assert i == 200;
}
procedure Thresholds2()
{
var i: int;
i := 100;
while (0 < i)
{
i := i - 1;
}
assert i == 0;
}
procedure Thresholds3()
{
var i: int;
i := 0;
while (i < 200)
{
i := i + 1;
}
assert i == 199; // error
}
procedure Thresholds4()
{
var i: int;
i := 0;
while (i + 3 < 203)
{
i := i + 1;
}
assert i * 2 == 400; // error: this would hold in an execution, but /infer:j is too weak to infer invariant i<=200
}
procedure UnaryNegation0() returns (x: int) // this was once buggy
{
x := -1;
loop_head:
x := x;
goto loop_head, after_loop;
after_loop:
assert x == -1;
}
procedure UnaryNegation1() returns (x: int) // this was once buggy
{
x := -1;
loop_head:
x := x;
goto loop_head, after_loop;
after_loop:
assert x == 1; // error
}
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