#include <bits/stdc++.h>
#define pb push_back
#define pf push_front
using namespace std;
#define F first
#define S second
typedef long long ll;
#define pii pair <int, int>
#define pll pair <ll, ll>
typedef long double ld;
const ll N = 2000 + 10;
const ll mod = 1e9 + 7;
ll um(ll a, ll b){
return ((1LL * a * b) % mod + mod) % mod;
}
ll subr(ll a, ll b){
return ((1LL * a - b) % mod + mod) % mod;
}
ll binpow(ll x, ll step){
ll res = 1LL;
while(step){
if(step & 1) res = um(res, x);
x = um(x, x);
step /= 2;
}
return res;
}
bool was[N];
int cnt, n, ans, f;
void calc(int index, int dir){
//cout << index << " "<< dir << endl;
if(cnt == n){
if(index == f) ans++;
return;
}
if(dir <= 0){
for(int i = index + 1; i <= n; i++){
if(was[i]) continue;
was[i] = true;
cnt++;
calc(i, 1);
cnt--;
was[i] = false;
}
}
if(dir >= 0){
for(int i = index - 1; i >= 1; i--){
if(was[i]) continue;
was[i] = true;
cnt++;
calc(i, -1);
cnt--;
was[i] = false;
}
}
}
int main() {
ios::sync_with_stdio(false);
cin.tie(NULL);
int s;
cin >> n >> s >> f;
was[s] = true;
cnt = 1;
calc(s, 0);
cout << ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Execution timed out |
2048 ms |
344 KB |
Time limit exceeded |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Execution timed out |
2048 ms |
344 KB |
Time limit exceeded |
4 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Execution timed out |
2048 ms |
344 KB |
Time limit exceeded |
4 |
Halted |
0 ms |
0 KB |
- |