Find Lexicographically Smallest String using C++

#include <bits/stdc++.h>

using namespace std;

string GetSmaller(string s1, string s2) {
    int n = (int) s1.size();
    int m = (int) s2.size();
    for (int i = 0; i < min(n, m); i++) {
        if (s1[i] < s2[i]) {
            return s1;
        } else if (s2[i] < s1[i]) {
            return s2;
        }
    }
    return (n < m ? s1 : s2);
}

int main() {
    string x, y;
    cin >> x >> y;
    cout << GetSmaller(x, y) << '\n';
    return 0;
}