제출 #236313

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
236313		LittleFlowers__	Tents (JOI18_tents)	C++17	100 / 100	144 ms	71068 KiB

tents

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define in ({int x=0;int c=getchar(),n=0;for(;!isdigit(c);c=getchar()) n=(c=='-');for(;isdigit(c);c=getchar()) x=x*10+c-'0';n?-x:x;})
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rnd(int l,int r){return l+rng()%(r-l+1);}
#define fasty ios_base::sync_with_stdio(0),cin.tie(0);
#define forinc(a,b,c) for(int a=b,_c=c;a<=_c;++a)
#define fordec(a,b,c) for(int a=b,_c=c;a>=_c;--a)
#define forv(a,b) for(auto&a:b)
#define fi first
#define se second
#define pb push_back
#define ii pair<int,int>
#define mt make_tuple
#define all(a) a.begin(),a.end()
#define reset(f, x) memset(f, x, sizeof(f))
#define bit(x,i) ((x>>(i-1))&1)
#define on(x,i) (x|(1ll<<(i-1)))
#define off(x,i) (x&~(1<<(i-1)))
#define gg exit(0);

const int N=3010,
          M=1000000007;

int m,n;
int f[N][N];

void add(int &a,int b){
    a+=b; a%=M;
}

main(){
    #define task "1"
    //freopen(task".inp","r",stdin);
    //freopen(task".out","w",stdout);

    m=in,n=in;
    forinc(i,0,m) forinc(j,0,n) if(i>0 && j>0){
        add(f[i][j],f[i-1][j]);
        add(f[i][j],f[i-1][j-1]*j*4);
        if(i>1 && j>0) add(f[i][j],f[i-2][j-1]*(i-1)*j);
        if(j>1 && i>0) add(f[i][j],f[i-1][j-2]*j*(j-1)/2);
    } else f[i][j]=1;
    cout<<(f[m][n]-1+M)%M;
}

컴파일 시 표준 에러 (stderr) 메시지

tents.cpp:33:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^

• Subtask 1: 48 / 48
• Subtask 2: 52 / 52