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/* Annotations in C programs */
/*W logic p : int -> prop */
/*@ requires x == 0 ensures \result == 1 */
int f(int x) {
return x+1;
}
/*W external h : int -> int */
int g();
/*@ ensures \result > 0 */
int g() {
int s = 0;
int i = 0;
/*@ assert s == 0 */;
/*@ invariant 0 <= i <= 10 variant 10 - i */
while (i < 10)
{
s += i++;
}
}
/* recursive function with a variant */
/*@ ensures n >= 0 // variant n
@*/
int fact(int n) {
return n == 0 ? 1 : n * fact(n-1);
}
void h() {
int i = 1000;
/*@ invariant i >= 0 variant i */
do i--; while (i > 0);
{
int j = 0;
/*@ assert j == 0 */;
/*@ invariant i >= 0 variant i */
for (; j < 10; j++) i += j;
}
}
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