/* VERIFY_OPTS: --symbolic --sequential */
/* TAGS: sym c */
/* CC_OPTS: */

extern void __VERIFIER_error() __attribute__ ((__noreturn__));

/*
 * Recursive implementation multiplication by repeated addition
 * Check that this multiplication is commutative
 *
 * Author: Jan Leike
 * Date: 2013-07-17
 *
 */

// V: small.5 CC_OPT: -DNUM=5
// V: big.100 CC_OPT: -DNUM=100 TAGS: big
// V: big.1000 CC_OPT: -DNUM=1000 TAGS: big
// V: big.46340 CC_OPT: -DNUM=46340 TAGS: big

extern int __VERIFIER_nondet_int(void);

// Multiplies two integers n and m
int mult(int n, int m) {
    if (m < 0) {
        return mult(n, -m);
    }
    if (m == 0) {
        return 0;
    }
    return n + mult(n, m - 1);
}

int main() {
    int m = __VERIFIER_nondet_int();
    if (m < 0 || m > NUM) {
        return 0;
    }
    int n = __VERIFIER_nondet_int();
    if (n < 0 || n > NUM) {
        return 0;
    }
    int res1 = mult(m, n);
    int res2 = mult(n, m);
    if (res1 != res2 && m > 0 && n > 0) {
        ERROR: __VERIFIER_error();
    } else {
        return 0;
    }
}