#include <bits/stdc++.h>
using namespace std;
using ll = long long;
ll calc(ll N, ll M) {
    if (N >= M) {
        return calc(M - 1, M);
    }
    if (N == 0) {
        return 0;
    }
    ll ka = 1, pr = 1, sum = 0;
    for (ll i = 1; i <= N; i ++) {
        ka = (ka * i) % M;
        pr = (pr * i) % M;
        sum = (sum + pr) % M;
    }
    return sum;
}
int main () {
    ll l, r, m;
    cin >> l >> r >> m;
    cout << ((calc(r, m) - calc(l - 1, m) + m) % m) << endl;
}