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13358.cpp
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13358.cpp
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#include <iostream>
using namespace std;
long long power(long long base, long long exp, long long mod) {
long long ret = 1;
while (exp) {
if (exp & 1) ret = ret * base % mod;
base = base * base % mod;
exp >>= 1;
}
return ret;
}
long long phi(long long x) {
long long ret = x;
for (long long i=2; i*i<=x; i++) {
if (x % i) continue;
ret -= ret / i;
while (!(x % i)) x /= i;
}
if (x > 1) ret -= ret / x;
return ret;
}
long long calc(long long n, long long m) {
if (m == 1) return 0;
if (n == 1) return 1;
if (n < 4) return power(n, n-1, m);
if (n == 4) return power(n, 9, m);
return power(n, phi(m) + calc(n-1, phi(m)), m);
}
void solve(void) {
long long n, m; cin >> n >> m;
cout << calc(n, m);
}
int main(void) {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
return 0;
}