#include<bits/stdc++.h>
using namespace std;
#ifdef ONPC
#include"debug.h"
#else
#define debug(...) 42
#endif
#define endl '\n'
#define ll long long
#define pii pair<int,int>
#define F first
#define S second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
const int mod = 1e9 + 7;
const int MAXN = 202;
const int inf = 0x3f3f3f3f;
const ll INF = 0x3f3f3f3f3f3f3f3f;
int dp[MAXN][MAXN][MAXN][2];
int n, cs, cf;
void solve(){
dp[1][1][1][0] = dp[1][1][1][1] = 1;
for (int i = 2; i <= n ; i++){
for (int j = 1; j <= i; j++){
for (int k = 1; k <= i; k++){
if (j == k) continue;
for (int l = 1; l < k; l++){
dp[i][j][k][1] += dp[i - 1][j - (k <= j)][l][0];
}
for (int l = k; l <= i; l++){
dp[i][j][k][0] += dp[i - 1][j - (k <= j)][l][1];
}
dp[i][j][k][0] %= mod;
dp[i][j][k][1] %= mod;
}
}
}
//for (int i = 1; i <= n; i++){
//for (int j = 1; j <= n; j++){
//debug(i, j, dp[n][i][j][0] + dp[n][i][j][1]);
//cout << dp[n][i][j][0] + dp[n][i][j][1] << ' ';
//}
//cout << endl;
//}
cout << dp[n][cs][cf][0] + dp[n][cs][cf][1] << endl;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n >> cs >> cf;
solve();
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Incorrect |
1 ms |
2908 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Incorrect |
1 ms |
2908 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2396 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Incorrect |
1 ms |
2908 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |