Can someone explain me the output of this simple program in C++?

While debugging an issue in our codebase, I stumbled upon a problem which is quite similar to this sample problem below

#include <iostream>
#include <vector>

int main() {
    std::vector<int> v;
    int MAX = 100;
    int result = (v.size() - 1) / MAX;
    std::cout << result << std::endl;
    return 0;
}

I would expect the output of the program should be 0 but it's -171798692.

Can someone help me understand this?