Submission #851887

#	Time	Username	Problem	Language	Result	Execution time	Memory
851887		vjudge1	Magneti (COCI21_magneti)	C++17	0 / 110	1 ms	604 KiB

Main

#pragma GCC optimize("unroll-loops,Ofast,O3")
#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define spc << " " <<
#define endl "\n"
#define all(x) x.begin(), x.end()
#define ll long long
#define int long long
#define ii pair<int,int>
#define vi vector<int>
#define vii vector<ii>
#define st first
#define nd second
#define inf 1000000009
#define MOD 1000000007
using namespace std;




int fact[20005];

int mult(int x, int y){
    return ((x%MOD)*(y%MOD))%MOD;
}
void init(){
    fact[0]=1;
    for(int i=1; i<=20003; i++) fact[i] = mult(fact[i-1], i);
}
int add(int x, int y){
    if(x+y>=MOD) return x+y-MOD;
    return x+y;
}
int fst(int base, int p){
    int res=1;
    while(p>0){
        if(p%2){
            res*=base;
            res%=MOD;
            p--;
        }
        base*=base;
        base%=MOD;
        p/=2;
    }
    return res;
}
int divi(int x, int y){
    y = fst(y, MOD-2);
    return mult(x, y);
}







void solve(){
    init();

    int n,l; cin >> n >> l;
    int r;
    for(int i=1; i<=n; i++) cin >> r;
    int k = (l-(1+((n-1)*r)));
    cerr << k << endl;
    int ans = divi(fact[add(n, k)], fact[k]);
    cout << ans << endl;
}



signed main(){
    ios_base::sync_with_stdio(false);cin.tie(0);
    #ifdef Local
    freopen("in","r",stdin);
    freopen("out","w",stdout);
    #endif

    ll t=1;
    //cin >> t;
    while(t--) solve();
}

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