#include <bits/stdc++.h>
using namespace std;
const unsigned long long MOD = 1e9 + 7;
unsigned long long power(unsigned long long exp) {
if (exp == 0) return 1;
if (exp % 2 == 0) {
unsigned long long x = power(exp / 2);
return (x * x) % MOD;
}
return (2 * power(exp - 1)) % MOD;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
unsigned long long n, k, s = 0;
cin >> n >> k;
k--;
for (unsigned long long mask = 0; mask < 64; mask++) {
if (k & (1LL << mask)) s = (s + power(n - 1 - mask)) % MOD;
}
cout << (s + 1) % MOD << endl;
return 0;
}
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |
# | Verdict | Execution time | Memory | Grader output |
---|
Fetching results... |