Book writing

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main() {
    ll n,m;
    cin>>n>>m;
    ll ans = 1;
    --n;
    ll q = 3;
    for(;n; n/=2) {
	if(n&1) {
	    ans = ans*q%m;
	}
	q = q*q%m;
    }
    cout<<ans%m<<'\n';
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED