Submission #1277570

#	Time	Username	Problem	Language	Result	Execution time	Memory
1277570		vuquangsang	Magneti (COCI21_magneti)	C++20	10 / 110	1 ms	580 KiB

Main

#include <bits/stdc++.h>
using namespace std;

#define     el "\n"
#define     FOR(i,a,b) for(int i = (a), _b = (b); i <= _b; i++)
#define     FORD(i,a,b) for(int i = (a), _b = (b); i >= _b; i--)
#define     pb push_back
#define     fi first
#define     se second
#define     all(x) x.begin(),x.end()
#define     lg(x) __lg(x)
#define     alla(a,n) a+1,a+n+1
#define     ll long long


template <class T> bool maxi(T &x, T y) { if(x < y) { x = y ; return true ;} return false;}
template <class T> bool mini(T &x, T y) { if(x > y) { x = y ; return true ;} return false;}

const int sm = 1e9 + 7;
const int N = 1e4 + 2;

int n, r[N], L;
ll fac[N], inv_fac[N];
int lim = 1e4;
ll Pow(int a, int n)
{
    if(!n) return 1;
    ll res = Pow(a, n / 2);
    res = 1LL * res * res % sm;
    if(n & 1) res = 1LL * res * a % sm;
    return res;
}
void prepare()
{
    fac[0] = inv_fac[0] = 1;
    FOR(i, 1, lim) fac[i] = 1LL * fac[i - 1] * i % sm;
    inv_fac[lim] = Pow(fac[lim], sm - 2);
    FORD(i, lim - 1, 1) inv_fac[i] = 1LL * inv_fac[i + 1] * (i + 1) % sm;
}
ll C(int k, int n)
{
    if(k < 0 || k > n) return 0;
    return 1LL * fac[n] * inv_fac[k] % sm * inv_fac[n - k] % sm;
}
void inp()
{
    cin >> n >> L;
    FOR(i, 1, n) cin >> r[i];
    prepare();
}

/* Try your best
    No regrets */

namespace subtask_1
{

    void slv()
    {
        ll res = 1LL * fac[n] * C(n, L - ((n - 1) * r[1] + 1) + n) % sm;
        cout << res;
    }
}

/* Code slowly, think carefully */

main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);

    #define __Azul__ "magneti"
    if(fopen(__Azul__".inp", "r")) {
        freopen(__Azul__".inp", "r", stdin);
        freopen(__Azul__".out", "w", stdout);
    }

    bool qs = 0;

    int T = 1;
    if(qs) cin >> T;
    while(T--) {
        inp();
        subtask_1::slv();
    }

    cerr << "\nTime" << 0.001 * clock() << "s "; return 0;


}

Compilation message (stderr)

Main.cpp:67:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   67 | main()
      | ^~~~
Main.cpp: In function 'int main()':
Main.cpp:73:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |         freopen(__Azul__".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:74:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |         freopen(__Azul__".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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