#pragma GCC optimize("O3", "inline")
#include <bits/stdc++.h>
using namespace std;
#define ins insert
#define pb push_back
#define int long long int
#define pii pair<int, int>
#define endl '\n'
#define drop(x) cout<<(x)<<endl; return;
#define all(x) x.begin(),x.end()
const int mod = 1e9 +7, sze = 1e5+10, inf = 2e18, prime = 23;
int dp[2005][2005];
void mal(){
dp[1][1]=1;
int n,a,b;cin>>n>>a>>b;
for(int i=2;i<=n;i++){
for(int j=1;j<=n;j++){
if(i==a || i==b){
dp[i][j] = (dp[i][j] + dp[i-1][j-1] + dp[i-1][j] +mod)%mod;
}
else{
dp[i][j]= (dp[i-1][j+1]*j + dp[i][j] + mod)%mod;
dp[i][j] = (dp[i][j] + dp[i-1][j-1] * (j - (i>a) - (i>b)) + mod)%mod; // a ni gormusuk, a dan arxaya qoyammariq, b ni gormusuk, b den arxaya qoyammariq, 2 hours
}
}
}
drop(dp[n][1]);
}
signed main() {
cin.tie(0)->sync_with_stdio(0);
int tt = 1;
// cin>>tt;
while(tt--){
mal();
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
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 |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
604 KB |
Output is correct |
5 |
Correct |
0 ms |
604 KB |
Output is correct |
6 |
Correct |
0 ms |
604 KB |
Output is correct |
7 |
Correct |
0 ms |
604 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
0 ms |
604 KB |
Output is correct |
10 |
Correct |
1 ms |
604 KB |
Output is correct |
11 |
Correct |
0 ms |
604 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 |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
604 KB |
Output is correct |
5 |
Correct |
0 ms |
604 KB |
Output is correct |
6 |
Correct |
0 ms |
604 KB |
Output is correct |
7 |
Correct |
0 ms |
604 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
0 ms |
604 KB |
Output is correct |
10 |
Correct |
1 ms |
604 KB |
Output is correct |
11 |
Correct |
0 ms |
604 KB |
Output is correct |
12 |
Correct |
1 ms |
1372 KB |
Output is correct |
13 |
Correct |
1 ms |
1372 KB |
Output is correct |
14 |
Correct |
1 ms |
1372 KB |
Output is correct |
15 |
Correct |
1 ms |
1372 KB |
Output is correct |
16 |
Correct |
1 ms |
1372 KB |
Output is correct |
17 |
Correct |
1 ms |
1372 KB |
Output is correct |
18 |
Correct |
1 ms |
1372 KB |
Output is correct |
19 |
Correct |
1 ms |
1372 KB |
Output is correct |
20 |
Correct |
1 ms |
1372 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 |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
604 KB |
Output is correct |
5 |
Correct |
0 ms |
604 KB |
Output is correct |
6 |
Correct |
0 ms |
604 KB |
Output is correct |
7 |
Correct |
0 ms |
604 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
0 ms |
604 KB |
Output is correct |
10 |
Correct |
1 ms |
604 KB |
Output is correct |
11 |
Correct |
0 ms |
604 KB |
Output is correct |
12 |
Correct |
1 ms |
1372 KB |
Output is correct |
13 |
Correct |
1 ms |
1372 KB |
Output is correct |
14 |
Correct |
1 ms |
1372 KB |
Output is correct |
15 |
Correct |
1 ms |
1372 KB |
Output is correct |
16 |
Correct |
1 ms |
1372 KB |
Output is correct |
17 |
Correct |
1 ms |
1372 KB |
Output is correct |
18 |
Correct |
1 ms |
1372 KB |
Output is correct |
19 |
Correct |
1 ms |
1372 KB |
Output is correct |
20 |
Correct |
1 ms |
1372 KB |
Output is correct |
21 |
Correct |
4 ms |
6236 KB |
Output is correct |
22 |
Correct |
4 ms |
7004 KB |
Output is correct |
23 |
Correct |
5 ms |
7772 KB |
Output is correct |
24 |
Correct |
21 ms |
31836 KB |
Output is correct |
25 |
Correct |
28 ms |
31740 KB |
Output is correct |
26 |
Correct |
22 ms |
31572 KB |
Output is correct |
27 |
Correct |
28 ms |
31580 KB |
Output is correct |
28 |
Correct |
15 ms |
23840 KB |
Output is correct |