Submission #535826

#	Time	Username	Problem	Language	Result	Execution time	Memory
535826		DJ035	Building 4 (JOI20_building4)	C++17	0 / 100	2 ms	468 KiB

building4

#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,avx,avx2")
#include <bits/stdc++.h>
#define MEM 2222
#define sanic ios_base::sync_with_stdio(0)
#define x first
#define y second
#define pf push_front
#define pb push_back
#define all(v) v.begin(), v.end()
#define sz size()
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pi;
const ll INF = 1e17+7;
const ll MOD = 998244353;
ll gcd(ll a, ll b){
    if(a%b) return gcd(b, a%b);
    return b;
}
ll t,n,m;
ll a[MEM],b[MEM];
ll dp[MEM][MEM][2];
void tr(ll x, ll y, ll z){
    if(!x) return;
    if(z){
        if((dp[x-1][y][0]) && (a[x-1]<=b[x])) tr(x-1, y, 0);
        else tr(x-1, y, 1);
        cout << 'B';
    }
    else{
        if((dp[x-1][y-1][0]) && (a[x-1]<=a[x])) tr(x-1, y-1, 0);
        else tr(x-1, y-1, 1);
        cout << 'A';
    }

}
signed main(){
    sanic; cin.tie(0);
    cin >> n;
    n<<=1;
    for(int i=1; i<=n; i++)
        cin >> a[i];
    for(int i=1; i<=n; i++)
        cin >> b[i];
    dp[0][0][0] = dp[0][0][1] = 1;
    for(int i=1; i<=n; i++){
        for(int j=0; j<=i; j++){
            if(j) dp[i][j][0] = ((dp[i-1][j-1][0]) && (a[i-1]<=a[i]))|((dp[i-1][j-1][1]) && (b[i-1]<=a[i]));
            dp[i][j][1] = ((dp[i-1][j][0]) && (a[i-1]<=b[i]))|((dp[i-1][j][1]) && (b[i-1]<=b[i]));
        }
    }
    if(dp[n][n/2][0]) tr(n, n/2, 0);
    else if(dp[n][n/2][1]) tr(n, n/2, 1);
    else cout << -1;
}

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