답안 #773052

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
773052 2023-07-04T14:25:27 Z davitmarg Power Plant (JOI20_power) C++17
0 / 100
8 ms 11988 KB
/*
DavitMarg
In pr honky-tonk,
Down in Mexico
*/
#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <string>
#include <cstring>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <queue>
#include <bitset>
#include <stack>
#include <cassert>
#include <iterator>
#include <random>
#include <chrono>
#define mod 1000000007ll
#define LL long long
#define LD long double
#define MP make_pair    
#define PB push_back
#define all(v) v.begin(), v.end()
#define fastIO ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
using namespace std;

const int N = 500005;

int n;
string s;
vector<int> g[N];
int dp[N], dp2[N];
int ans = 0;

void dfs(int v, int p)
{
    dp[v] = s[v] - '0';
    int sum = 0;
    for(int i = 0; i < g[v].size(); i++)
    {
        int to = g[v][i];
        if(to == p)
            continue;
        dfs(to, v);
        sum += dp[to];
    }
    dp2[v] = dp[v] = max(dp[v], sum - (s[v] - '0'));
}

void dfs2(int v, int p)
{
    dp2[v] = s[v] - '0';
    int sum = 0;
    int mx = 0;
    for(int i = 0; i < g[v].size(); i++)
    {
        int to = g[v][i];
        if(to == p)
            continue;
        sum += dp[to];
        mx = max(dp[to], mx);
    }

    if(p > -1)
    {
        sum += dp2[p];
        mx = max(dp2[p], mx);
    }

    dp2[v] = max(dp2[v], sum - (s[v] - '0'));
    ans = max(ans, max(dp2[v], (s[v] - '0') + mx));

    for(int i = 0; i < g[v].size(); i++)
    {
        int to = g[v][i];
        if(to == p)
            continue;
        dfs(to, v);
    }

    dp2[v] = dp[v];
}

LL myRand()
{
    return ((LL)rand() << 16) + rand();
}

void solve()
{
    cin >> n;
    for(int i = 1; i <= n - 1; i++)
    {
        int a, b;
        cin >> a >> b;
        g[a].PB(b);
        g[b].PB(a);
    }
    cin>>s;
    s = '#' + s;

    vector<int> p;
    for(int i = 1; i <= n; i++)
        if(s[i] == '1')
            p.PB(i);

    int st = p[0];
    dfs(st, -1);
    dfs2(st, -1);
    cout << ans << endl;
}

int main()
{
    fastIO;
    int T = 1;
    //cin >> T;
    while (T--)
    {
        solve();
    }

    return 0;
}

/*


cd /mnt/d/Davit/Projects/VSCode; g++ -std=c++17 -O2 -Wall -Wextra -Ddeath -Wshadow source.cpp -o orz; ./orz; rm orz

*/

Compilation message

power.cpp: In function 'void dfs(int, int)':
power.cpp:45:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   45 |     for(int i = 0; i < g[v].size(); i++)
      |                    ~~^~~~~~~~~~~~~
power.cpp: In function 'void dfs2(int, int)':
power.cpp:61:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   61 |     for(int i = 0; i < g[v].size(); i++)
      |                    ~~^~~~~~~~~~~~~
power.cpp:79:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |     for(int i = 0; i < g[v].size(); i++)
      |                    ~~^~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 8 ms 11988 KB Output is correct
3 Correct 6 ms 11980 KB Output is correct
4 Correct 8 ms 11988 KB Output is correct
5 Correct 6 ms 11988 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Incorrect 6 ms 11988 KB Output isn't correct
8 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 8 ms 11988 KB Output is correct
3 Correct 6 ms 11980 KB Output is correct
4 Correct 8 ms 11988 KB Output is correct
5 Correct 6 ms 11988 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Incorrect 6 ms 11988 KB Output isn't correct
8 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 8 ms 11988 KB Output is correct
3 Correct 6 ms 11980 KB Output is correct
4 Correct 8 ms 11988 KB Output is correct
5 Correct 6 ms 11988 KB Output is correct
6 Correct 6 ms 11988 KB Output is correct
7 Incorrect 6 ms 11988 KB Output isn't correct
8 Halted 0 ms 0 KB -