Hello 2018 A - Modular Exponentiation

#include<iostream>
#include<algorithm>
#include<iomanip>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<string>
#include<cmath>
#include<set>
#include<queue>
#include<stack>
#include<map>
#define PI acos(-1.0)
#define in freopen("in.txt", "r", stdin)
#define out freopen("out.txt", "w", stdout)
#define kuaidian ios::sync_with_stdio(0);

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
const int maxn = 1000 + 7, maxd = 1e5 + 7;

const ll mod = 1e9 + 7;
const int INF = 0x7f7f7f7f;

int n, m;

int main() {

scanf("%d %d", &n, &m);
if(n >= 27) {
printf("%d", m);
}
else {
int mod = 1;
for(int i = 1; i <= n; ++i) {
mod *= 2;
}
printf("%d", m%mod);
}

return 0;
}