Submission #1114917

#	Time	Username	Problem	Language	Result	Execution time	Memory
1114917		Younis_Dwai	Building 4 (JOI20_building4)	C++14	0 / 100	10 ms	8784 KiB

building4

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
#define endl "\n"
#define F first
#define S second
#define pb push_back
//#define int long long
#define in insert
#define mid (l+r)/2
#define in insert
using namespace std;
const int N=2e3+5;
bool dp[2*N][N][2];
int b[N],a[N],n;
//string ans="";
void get(int id ,int done ,int cur){
     if(id==0) return ;
     if(cur==0){
        if(dp[id-1][done-1][0] && a[id-1]<=a[id]) get(id-1,done-1,0);
        else get(id-1,done-1,1);
        cout<<'A';
     }
     else{
        if(dp[id-1][done][0] && a[id-1]<=b[id]) get(id-1,done,0);
        else get(id-1,done,1);
        cout<<'B';
     }
     return ;
}
int32_t main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);
    cin>>n;
    for(int i=1;i<=n*2;i++) cin>>a[i];
    for(int i=1;i<=n*2;i++) cin>>b[i];
    dp[0][0][0]=1;
    for(int i=1;i<=2*n;i++){
        for(int j=0;j<=n;j++){
            if(dp[i-1][j][0]){
               if(a[i-1]<=a[i]) dp[i][j+1][0]=1;
               if(a[i-1]<=b[i]) dp[i][j][1]=1;
            }
            if(dp[i-1][j][1]){
               if(b[i-1]<=a[i]) dp[i][j+1][0]=1;
               if(b[i-1]<=b[i]) dp[i][j][1]=1;
            }
        }
    }
    if(dp[2*n][n][0]+dp[2*n][n][1]==0) cout<<-1;
    else{
            if(dp[2*n][n][0]==1) get(2*n,n,0);
            else get(2*n,n,1);
    }
    return 0;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 89