Submission #113925

#	Time	Username	Problem	Language	Result	Execution time	Memory
113925		Mercenary	Calvinball championship (CEOI15_teams)	C++14	100 / 100	309 ms	692 KiB

teams

#include<bits/stdc++.h>

using namespace std;
#define taskname "A"
#define pb  push_back
#define mp  make_pair
#ifndef LOCAL
#define cerr if(0)cout
#endif

typedef long double ld;
typedef long long ll;
typedef pair<int,int> ii;
const int maxn = 1e4 + 5;
const int mod = 1e6 + 7;

int a[maxn] , ma[maxn];

int dp[2][maxn];
int n;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
        freopen(taskname".INP", "r",stdin);
        freopen(taskname".OUT", "w",stdout);
    }
    cin >> n;
    for(int i = 1 ; i <= n ; ++i)cin >> a[i];
    for(int i = 1 ; i <= n ; ++i)ma[i] = max(ma[i - 1] , a[i]);
    int res = 1;bool bit = 0;
    for(int j = 0 ; j <= n ; ++j){
        dp[0][j] = 1;
    }
    for(int i = n ; i >= 1 ; --i){
//        res += (ll)(a[i] - 1) * dp[bit][ma[i - 1]] % mod;
//        cout << i << " " << dp[bit][ma[i]] << endl;
        if(res >= mod)res -= mod;
        bit ^= 1;
        for(int j = 1 ; j <= n ; ++j){
            dp[bit][j] = dp[bit ^ 1][j + 1] + (ll)j * dp[bit ^ 1][j] % mod;
            if(dp[bit][j] >= mod)dp[bit][j] -= mod;
            if(j < a[i]){
                res += dp[bit ^ 1][max(ma[i - 1],j)];
                if(res >= mod)res -= mod;
//                cout << i << " " << max(ma[i - 1] , )
            }
        }
    }
    cout << res;
}

Compilation message (stderr)

teams.cpp: In function 'int main()':
teams.cpp:27:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(taskname".INP", "r",stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
teams.cpp:28:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(taskname".OUT", "w",stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10