Submission #724645

#	Time	Username	Problem	Language	Result	Execution time	Memory
724645		TheSahib	Magneti (COCI21_magneti)	C++17	20 / 110	1086 ms	238744 KiB

Main

#include <bits/stdc++.h>
 
#pragma GCC optimize("O3")
 
#define ll long long
#define oo 1e9 + 9
#define pii pair<int, int>
 
using namespace std;

const int MOD = 1e9 + 7;
const int MAX = 1e4 + 100;
int comb[MAX][MAX];

void preCalc(){
    comb[0][0] = 1;
    for (int i = 1; i < MAX; i++)
    {
        comb[i][0] = comb[i][i] = 1;
        for (int j = 1; j < i; j++)
        {
            comb[i][j] = comb[i - 1][j] + comb[i - 1][j - 1];
            comb[i][j] %= MOD;
        }
    }
}

int main(){
    preCalc();
    int n, l; cin >> n >> l;
    int arr[n];
    for (int i = 0; i < n; i++)
    {
        cin >> arr[i];
    }
    int idx[n];
    for (int i = 0; i < n; i++)
    {
        idx[i] = i;
    }
    

    int ans = 0;
    do{
        int d = 1;
        for (int i = 0; i < n - 1; i++)
        {
            d += max(arr[idx[i]], arr[idx[i + 1]]);
        }
        if(d > l) continue;
        ans += comb[l - d + n][n];
        ans %= MOD;
    }
    while(next_permutation(idx, idx + n));
    cout << ans << '\n';
}

• Subtask 1: 0 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 50