제출 #744971

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
744971		sword060	Magneti (COCI21_magneti)	C++17	10 / 110	1095 ms	524288 KiB

Main

#include <bits/stdc++.h>
using namespace std;
const int N=10005,M=1e9+7;
int x,k,dp[N][1<<10][11],dp2[N][51],a[N];
int rec(int i,int msk,int lst){
  if(i>k)return 0;
  if((msk^(1<<lst))==0)return k-i+1;
  if(~dp[i][msk][lst])return dp[i][msk][lst];
  int ret=rec(i+1,msk,lst);
  if(ret>=M)ret-=M;
  for(int nxt=0;nxt<x;nxt++)
    if(msk&(1<<nxt)){
      ret+=rec(i+max(a[lst+1],a[nxt+1]),msk^(1<<lst),nxt);
      if(ret>=M)ret-=M;
    }
  return dp[i][msk][lst]=ret;
}
int rec2(int i,int j){
  if(i>k)return 0;
  if(j==1)return k-i+1;
  if(~dp2[i][j])return dp2[i][j];
  long long ret=(((rec2(i+a[1],j-1)*1LL*j)%M)+(rec2(i+1,j)%M))%M;
  return dp2[i][j]=ret;
}
int main(){
  ios::sync_with_stdio(0);cin.tie(0);
  cin>>x>>k;
  bool f=1;
  for(int i=1;i<=x;i++)cin>>a[i],f&=(a[i]==a[1]);
  if(!f){
    memset(dp,-1,sizeof(dp));
    long long sum=0;
    for(int i=0;i<x;i++)sum=(sum+rec(1,(1<<x)-1,i))%M;
    cout<<sum;
  }else{
    memset(dp2,-1,sizeof(dp2));
    cout<<rec2(1,x);
  }
  return 0;
}

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