nudt-compiler-cpp/test/test_case/testdata2026/performance/crc1.sy

int crc32table[256];
  
int a[100020];

int _and(int a, int b) {
    int bit_a, bit_b;
    int len = 32, result = 0, power = 1;
    
    while (len) {
        bit_a = a % 2;
        bit_b = b % 2;
        a = a / 2;
        b = b / 2;
        if (bit_a == 1 && bit_b == 1) {
            result = result + power;
        }
        power = power * 2;
        len = len - 1;
    }

    return result;
}

int _xor(int a, int b) {
    int bit_a, bit_b;
    int len = 32, result = 0, power = 1;
    
    while (len) {
        bit_a = a % 2;
        bit_b = b % 2;
        a = a / 2;
        b = b / 2;
        if (bit_a != bit_b) {
            result = result + power;
        }
        power = power * 2;
        len = len - 1;
    }

    return result;
}

int rotr8(int x) {
  return x / 256;
}

int crc32(int crc, int p[], int len)
{
    int i = 0;
    int index;
	while (i < len) {
        index = _xor(_and(crc, 255), p[i]);
        crc = _xor(rotr8(crc), crc32table[index]);
        i = i + 1;
    }
	return crc;
}

int main() {
    int n = getarray(a);
    int crc = 0;
    int ans;
    int i = 0;
    while (i < 256) {
    	  crc32table[i] = 19260817 + i;
	  i = i + 1;
    }
    starttime();
    while (n) {
        ans = crc32(crc, a, n) % 19260817;
        n = n - 1;
    }
    stoptime();
    
    putint(ans);
    putch(10);
    
    return 0;
}