Submission #772609

#	Time	Username	Problem	Language	Result	Execution time	Memory
772609		CyberCow	Power Plant (JOI20_power)	C++17	47 / 100	22 ms	16244 KiB

power

//#include <bits/stdc++.h>
#include <random>
#include <algorithm>
#include <bitset>
#include <chrono>
#include <cmath>
#include <deque>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>
#include <chrono>
#define fr first
#define sc second
#define ad push_back
using namespace std;
using ll = long long;
mt19937 rnd(348502);
const int N = 2005;
int n;
vector<int> v[N];
int dp[N][N], a[N];

void Dfs(int g, int p)
{
    for (auto to : v[g])
    {
        if (to != p)
        {
            Dfs(to, g);
        }
    }
    if (a[g] == 0)
    {
        int gum = 0;
        for (auto to : v[g])
        {
            if (to != p)
            {
                int ma = 0;
                for (int i = 0; i <= n; i++)
                {
                    dp[g][i] = max(dp[g][i], dp[to][i]);
                    ma = max(ma, dp[to][i] - 2 * i);
                }
                gum += ma;
            }
        }
        dp[g][0] = max(gum, dp[g][0]);
    }
    else
    {
        int gum = 0;
        for (auto to : v[g])
        {
            if (to != p)
            {
                int ma = 0;
                for (int i = 0; i <= n; i++)
                {
                    dp[g][1] = max(dp[g][1], dp[to][i] - 2 * i + 1);
                    dp[g][i + 1] = max(dp[to][i], dp[g][i + 1]);
                    ma = max(ma, dp[to][i] - 2 * i);
                }
                gum += ma;
            }
        }
        dp[g][0] = max(dp[g][0], gum - 1);
        dp[g][0] = max(dp[g][0], 1);
    }
}

void solve()
{
    int i, j, x, y;
    cin >> n;
    for ( i = 0; i < n - 1; i++)
    {
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    char c;
    for ( i = 1; i <= n; i++)
    {
        cin >> c;
        a[i] = c - '0';
    }
    Dfs(1, -1);
    int ans = 0;
    for (int i = 0; i <= n; i++)
    {
        ans = max(dp[1][i], ans);
    }
    cout << ans;
}


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int tt = 1;
    //cin >> tt;
    while (tt--) {
        solve();
    }
    return 0;
}

Compilation message (stderr)

power.cpp: In function 'void solve()':
power.cpp:83:12: warning: unused variable 'j' [-Wunused-variable]
   83 |     int i, j, x, y;
      |            ^

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 0 / 53