제출 #531970

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
531970		Killer2501	Magneti (COCI21_magneti)	C++14	60 / 110	106 ms	4780 KiB

Main

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define ull unsigned long long
#define pb push_back
#define pll pair<ll, ll>
#define pii pair<ll, int>
#define fi first
#define se second
using namespace std;
const int N = 1e4+2;
const int M = 52;
const int mod = 1e9+7;
const ll base = 75;
const ll inf = 1e16;
int n, lab[N], t, c[N+M], h[N], P[N][20], m, a[N], b[N+M], ans, d[N], k, lst[M][N], dp[M][N];
vector<int> adj[N];
vector<int> vi;
string s;
bool vis[N];
ll pw(ll k, ll n)
{
    ll total = 1;
    for(; n; n >>= 1)
    {
        if(n&1)total = total * k % mod;
        k = k * k % mod;
    }
    return total;
}
void add(int& x, int y)
{
    x += y;
    if(x >= mod)x -= mod;
}
int findp(int u)
{
    return lab[u] < 0 ? u : lab[u] = findp(lab[u]);
}
void hop(int u, int v)
{
    u = findp(u);
    v = findp(v);
    if(u == v)return;
    if(lab[u] > lab[v])swap(u, v);
    lab[u] += lab[v];
    lab[v] = u;
}
int C(int u, int v)
{
    if(u > v)return 0;
    return 1ll * b[v] * c[u] % mod * c[v-u] % mod;
}
void sol()
{
    cin >> n >> m;
    for(int i = 1; i <= n; i ++)cin >> a[i];
    b[0] = c[0] = 1;
    for(int i = 1; i <= m+n; i ++)b[i] = 1ll * b[i-1] * i % mod;
    c[m+n] = pw(b[m+n], mod-2);
    for(int i = m+n-1; i > 0; i --)c[i] = 1ll * c[i+1] * (i+1) % mod;
    sort(a+1, a+1+n);
    lst[1][1] = 1;
    for(int i = 2; i <= n; i ++)
    {
        memset(dp, 0, sizeof(dp));
        for(int j = 1; j < i; j ++)
        {
            for(int l = i-1; l <= m; l ++)
            {
                add(dp[j+1][l+1], lst[j][l]);
                add(dp[j][l+a[i]], 2ll * j * lst[j][l] % mod);
                if(j > 1 && l+a[i]*2-1 <= m)add(dp[j-1][l+a[i]*2-1], 1ll * j * (j-1) * lst[j][l] % mod);
            }
        }
        swap(dp, lst);
    }
    for(int i = 1; i <= m; i ++)add(ans, 1ll * lst[1][i] * C(n, m-i+n) % mod);
    cout << ans;
}
int main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
    #define task "test"
    if(fopen(task".inp", "r"))
    {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int test = 1;
    //cin >> test;
    while(test -- > 0)sol();
    return 0;
}
/*
1234
21
*/

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'int main()':
Main.cpp:89:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:90:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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