Submission #1108638

#	Time	Username	Problem	Language	Result	Execution time	Memory
1108638		cpptowin	NoM (RMI21_nom)	C++17	52 / 100	197 ms	32336 KiB

Main

#include <bits/stdc++.h>
#define fo(i, d, c) for (int i = d; i <= c; i++)
#define fod(i, c, d) for (int i = c; i >= d; i--)
#define maxn 1000010
#define N 1010
#define fi first
#define se second
#define pb emplace_back
#define en cout << "\n";
#define int long long
#define inf (int)1e18
#define bitcount(x) __builtin_popcountll(x)
#define pii pair<int, int>
#define vii vector<pii>
#define lb(x) x & -x
#define bit(i, j) ((i >> j) & 1)
#define offbit(i, j) (i ^ (1LL << j))
#define onbit(i, j) (i | (1LL << j))
#define vi vector<int>
#define all(x) x.begin(), x.end()
#define ss(x) (int)x.size()
#define UNIQUE(v) v.erase(unique(all(v)),v.end())
template <typename T1, typename T2>
bool minimize(T1 &a, T2 b)
{
    if (a > b)
    {
        a = b;
        return true;
    }
    return false;
}
template <typename T1, typename T2>
bool maximize(T1 &a, T2 b)
{
    if (a < b)
    {
        a = b;
        return true;
    }
    return false;
}
using namespace std;
const int nsqrt = 450;
const int mod = 1e9 + 7;
void add(int &x, int k)
{
    x += k;
    x %= mod;
    if(x < 0) x += mod;
}
void del(int &x, int k)
{
    x -= k;
    x %= mod;
    if(x < 0) x += mod;
}
int Pow(int a,int n)
{
    int ans = 1;
    for( ; n ; n >>= 1, a = ((a * a) % mod + mod) % mod) if(n & 1)
        {
            ans = ((ans * a) % mod + mod) % mod;
        }
    return ans;
}
int n,m;
int cnt[N];
int fact[maxn],inv[maxn];
int C(int k,int n) 
{
    if(k > n) return 0;
    return fact[n] * inv[k] % mod * inv[n - k] % mod;
}
main()
{
#define name "TASK"
    if (fopen(name ".inp", "r"))
    {
        freopen(name ".inp", "r", stdin);
        freopen(name ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n >> m;
    fo(i,0,2 * n - 1) cnt[i % m]++;
    fact[0] = 1;
    fo(i,1,maxn - 1) fact[i] = fact[i - 1] * i % mod;
    inv[maxn - 1] = Pow(fact[maxn - 1],mod - 2);
    fod(i,maxn - 2,0) inv[i] = inv[i + 1] * (i + 1) % mod;
    vi dp(2 * n + 1,0),f(2 * n + 1,0);
    dp[cnt[0]] = 1;
    int sum = cnt[0];
    fo(i,1,m - 1) 
    {
        for(int &it : f) it = 0;
        fo(j,0,cnt[i]) fo(k,j,sum)
        {
            add(f[k + cnt[i] - 2 * j],dp[k] * fact[j] % mod * C(j,cnt[i]) % mod * C(j,k) % mod);
        }
        dp = f;
        sum += cnt[i];
    }
    fo(i,1,n) dp[0] = dp[0] * 2 % mod;
    dp[0] = (dp[0] * fact[n]) % mod;
    cout << dp[0]; 
}

Compilation message (stderr)

Main.cpp:75:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   75 | main()
      | ^~~~
Main.cpp: In function 'int main()':
Main.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 ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:81:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   81 |         freopen(name ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 13 / 13
• Subtask 4: 18 / 18
• Subtask 5: 0 / 48