#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MOD = 1e9 + 7;
int binpow(int a, int b){
if(!b) return 1;
else if(b % 2 == 0){
int x = binpow(a, b / 2);
return (x * x) % MOD;
}else{
int x = binpow(a, b / 2);
x = (x * x) % MOD;
return (x * a) % MOD;
}
}
signed main(){
int n, k; cin >> n >> k;
int cnt = 0;
int ans = 1;
int pp = binpow(2, n - 1) % MOD;
while(k > 1){
if (k % 2 == 0) {
k--;
ans += pp;
ans %= MOD;
}
k -= (k - 1) / 2;
pp = (pp * binpow(2, MOD - 2) % MOD) % MOD;
pp %= MOD;
}
cout << ans << endl;
}
Compilation message
rack.cpp: In function 'int main()':
rack.cpp:21:9: warning: unused variable 'cnt' [-Wunused-variable]
21 | int cnt = 0;
| ^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
604 KB |
Output is correct |
7 |
Correct |
1 ms |
352 KB |
Output is correct |
8 |
Correct |
1 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
344 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
604 KB |
Output is correct |
7 |
Correct |
1 ms |
352 KB |
Output is correct |
8 |
Correct |
1 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 KB |
Output is correct |
12 |
Correct |
0 ms |
348 KB |
Output is correct |
13 |
Correct |
0 ms |
348 KB |
Output is correct |
14 |
Correct |
0 ms |
348 KB |
Output is correct |
15 |
Correct |
0 ms |
348 KB |
Output is correct |