#include <bits/stdc++.h>
using namespace std;
const long long mod = 1e9+7;
const int N = 2100, LG=10;
long long binpow(long long a, long long b, long long MOD) {
a%=MOD;
long long res = 1;
while(b) {
if(b&1){
res=(res*a)%MOD;
}
a=(a*a)%MOD;
b>>=1ll;
}
res%=MOD;
return res;
}
int dist[N][N];
int tmp;
vector<int> g[N];
void dfs(int at, int p=0) {
for(int to:g[at]) {
if(to == p)continue;
dist[tmp][to] = dist[tmp][at]+1;
dfs(to, at);
}
}
int main () {
cin.tie(0)->sync_with_stdio(0);
int q;
cin >> q;
while(q--) {
int n;
cin >> n;
memset(dist, 0, sizeof dist);
for(int i = 1;i<=n;i++) {
if(2*i <= n) {
g[i].push_back(2*i);
g[2*i].push_back(i);
}
if(2*i+1 <=n) {
g[i].push_back(2*i+1);
g[2*i+1].push_back(i);
}
}
for(int i = 1;i<=n;i++) {
tmp = i;
dfs(i, 0);
}
long long ans=0;
for(int i = 1;i<=n;i++) {
for(int j = 0;j<=n;j++) {
long long pw1 = 1, pw2=1;
int cnt=0;
for(int k = 1;k<=n;k++) {
if(dist[i][k] < j) {
pw1=(pw1*binpow(2, mod-2, mod))%mod;
}
else if(dist[i][k] == j) {
pw2=(pw2*binpow(2, mod-2, mod))%mod;
}
}
ans+=((pw1*(1-pw2))%mod*j)%mod;
ans%=mod;
ans+=mod;
ans%=mod;
}
}
ans=(ans*binpow(2,n, mod))%mod;
ans=(ans*binpow(binpow(2,n, mod)-1+mod, mod-2, mod))%mod;
cout << ans << "\n";
for(int i = 1;i<=n;i++) {
g[i].clear();
}
}
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:54:13: warning: unused variable 'cnt' [-Wunused-variable]
54 | int cnt=0;
| ^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
3067 ms |
17756 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
64 ms |
82404 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
65 ms |
82424 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
3067 ms |
17756 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |