#include <bits/stdc++.h>
using namespace std;
long long binpow(long long a, long long b)
{
    if (b == 0)
        return 1;
    long long res = binpow(a, b / 2);
    if (b % 2)
        return res * res * a;
    else
        return res * res;
}
int main()
{
    long long a, b, c;
    cin >> a >> b >> c;
    cout << a << '^' << b << ' ' << "mod" << ' ' << c << '=' << binpow(a, b) % c;
    return 0;
}

谢谢大佬指教