#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
#define MOD (1000000000+7)
ll fp(ll a, ll b){
ll res = 1;
while(b){
if(b&1) (res*=a)%=MOD;
(a*=a)%=MOD;
b>>=1;
}
return res;
}
int main(){
cin.tie(0); ios::sync_with_stdio(0);
ll n, k, ans=1;
cin >> n >> k;
for(ll i = n-1; i > 0; i--){
if(k&1){
k = (k>>1) + 1;
}else{
k >>= 1;
ans += fp(2, i);
}
(ans%=MOD);
(ans+=MOD)%=MOD;
}
cout << ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Incorrect |
1 ms |
204 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Incorrect |
1 ms |
204 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Incorrect |
1 ms |
204 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |