#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
int n, A[10005], dp[105][105][2];
const int mod = 1e6 + 7;
int c(int x, int cur, bool f){
if(x == n + 1)return 1;
if(dp[x][cur][f] != -1)return dp[x][cur][f];
int ans = 0;
if(cur < A[x])ans += c(x + 1, cur + 1, f & (cur + 1 == A[x]));
if(cur)ans += c(x + 1, cur, f & (cur == A[x]));
if(cur)ans += c(x + 1, cur, 0) * (cur - 1);
ans %= mod;
return dp[x][cur][f] = ans;
}
void solve(){
cin >> n;
for(int i = 1; i <= n; i++)cin >> A[i];
memset(dp, -1, sizeof(dp));
/*
dp[0][0][1] = 1;
for(int i = 1; i <= n; i++){
for(int j = 0; j <= n; j++)dp[i & 1][j] = 0;
for(int j = 1; j <= A[i]; j++){
dp[i & 1][j] = dp[(i - 1) & 1][j] * j + dp[(i - 1) & 1][j - 1];
dp[i & 1][j] %= mod;
}
}
int ans = 0;
for(int i = 1; i <= n; i++)ans += dp[1 & n][i], ans %= mod;
cout << ans;
*/
cout << c(1, 0, 1);
}
main(){
ios::sync_with_stdio(0);cin.tie(0);
int tc = 1;
//cin >> tc;
for(int tc1=1;tc1<=tc;tc1++){
// cout << "Case #" << tc1 << ": ";
solve();
}
}
Compilation message
teams.cpp:47:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
47 | main(){
| ^~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
600 KB |
Output is correct |
2 |
Correct |
1 ms |
600 KB |
Output is correct |
3 |
Correct |
0 ms |
604 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 |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
856 KB |
Output is correct |
2 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
1 ms |
604 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |