Submission #1101132

#	Time	Username	Problem	Language	Result	Execution time	Memory
1101132		InvMOD	Zapina (COCI20_zapina)	C++14	110 / 110	241 ms	2384 KiB

zapina

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


#define fi first
#define se second
#define gcd __gcd
#define sz(v) v.size()
#define pb push_back
#define pi pair<int,int>
#define all(v) (v).begin(), (v).end()
#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define REP(i, n) FOR(i, 1, n)
///#define int long long

using ll = long long;
using ld = long double;
using ull = unsigned long long;

template<typename T> bool ckmx(T &a, T b){if(a < b) return a = b, true; return false;}
template<typename T> bool ckmn(T &a, T b){if(a > b) return a = b, true; return false;}

const int N = 400;
const ll MOD = 1e9+7;
const ll INF = 1e18;


int n, dp[2][N][N], C[N][N];

int add(int a, int b){
    a += b;
    if(a >= MOD) a -= MOD;
    return a;
}

int mul(int a, int b){
    return (ll) a * b % MOD;
}

int get(int check, int rem, int cur){
    if(cur == n+1){
        if(rem != 0) return 0;
        return check;
    }
    if(rem == 0) return check;
    if(dp[check][rem][cur] != -1) return dp[check][rem][cur];

    int res = 0;
    FOR(i, 0, rem){
        ///How many different way to choose i from rem
        res = add(res, mul(C[rem][i], get((check | (cur == i)), rem - i, cur+1)));
    }
    return dp[check][rem][cur] = res;
}

void solve()
{
    cin >> n;
    memset(dp, -1, sizeof(dp));
    C[0][0] = 1;
    REP(i, n){
        FOR(j, 0, i){
            C[i][j] = C[i-1][j];
            if(j) C[i][j] = add(C[i][j], C[i-1][j-1]);
        }
    }

    cout << get(0, n, 1) <<"\n";
}

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

    #define name "InvMOD"
    if(fopen(name".INP", "r")){
        freopen(name".INP","r",stdin);
        freopen(name".OUT","w",stdout);
    }

    int t = 1; //cin >> t;
    while(t--) solve();
    return 0;
}

Compilation message (stderr)

zapina.cpp: In function 'int main()':
zapina.cpp:79:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |         freopen(name".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
zapina.cpp:80:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |         freopen(name".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 22 / 22
• Subtask 2: 33 / 33
• Subtask 3: 55 / 55