Submission #875640

#	Time	Username	Problem	Language	Result	Execution time	Memory
875640		hmm789	Cat Exercise (JOI23_ho_t4)	C++14	21 / 100	2029 ms	344064 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define INF 1000000000000000000
#define MOD 998244353
 
vector<int> adj[200000];
int mx[5000][5000], memo[5000][5000];
int dp(int x, int y) {
    if(x > y) return 0;
    if(memo[x][y] != -1) return memo[x][y];
    memo[x][y] = 0;
    if(x <= mx[x][y]-1) memo[x][y] = max(memo[x][y], dp(x, mx[x][y]-1)+mx[x][y]-mx[x][mx[x][y]-1]);
    if(mx[x][y]+1 <= y) memo[x][y] = max(memo[x][y], dp(mx[x][y]+1, y)+mx[mx[x][y]+1][y]-mx[x][y]);
    return memo[x][y];
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    int n, x, y;
    cin >> n;
    int p[n];
    for(int i = 0; i < n; i++) cin >> p[i];
    for(int i = 0; i < n-1; i++) {
        cin >> x >> y;
        x--; y--;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    for(int i = 0; i < n; i++) {
        for(int j = i; j < n; j++) {
            if(i == j) mx[i][j] = i;
            else if(p[mx[i][j-1]] > p[j]) mx[i][j] = mx[i][j-1];
            else mx[i][j] = j;
        }
    }
    memset(memo, -1, sizeof(memo));
    cout << dp(0, n-1);
}

• Subtask 1: 7 / 7
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 0 / 10
• Subtask 5: 0 / 20
• Subtask 6: 0 / 23
• Subtask 7: 0 / 26