Submission #588761

#	Time	Username	Problem	Language	Result	Execution time	Memory
588761		Loki_Nguyen	Power Plant (JOI20_power)	C++14	100 / 100	161 ms	31668 KiB

power

#include <bits/stdc++.h>
#define pll pair<ll, ll>
#define fi first
#define se second
#define pb push_back
#define task "test"
#define pii pair<pll, pll>
using namespace std;
using ll = int;
const int N = 2e5+5;
const ll mod = 1e8 + 7;
const ll base = 113;
const ll inf = 1e9;
int m, n, t, k, a[N], tong, d[N], dp[N], h[N], ans;
vector<int> adj[N];
string s;
int dfs(int u, int p = 0)
{
    if(dp[u] != -1)return dp[u];
    int sum = 0, cnt = 0, mx = 0;
    for(int v: adj[u])
    {
        if(v == p)continue;
        sum += dfs(v, u);
        mx = max(mx, dfs(v, u));
        ++cnt;
    }
    if(s[u] == '1')
    {
        ans = max(ans, mx+1);
        sum = max(sum-1, 1);
    }
    ans = max(ans, sum);
    return dp[u] = sum;
}
void sol()
{
    cin >> n;
    for (int i = 1; i < n; i++)
    {
        int x, y;
        cin >> x >> y;
        adj[x].pb(y);
        adj[y].pb(x);
    }
    cin >> s;
    s = " " + s; 
    fill_n(dp, n+1, -1);
    dfs(1);
    cout << ans;
}
int main()   
{
    ios_base::sync_with_stdio(0); 
    cin.tie(0);
    cout.tie(0);
    if (fopen(task ".inp", "r"))
    {
        freopen(task ".inp", "r", stdin);
        freopen(task ".out", "w", stdout);
    }
    int ntest = 1;
    // cin >> ntest;   
    while (ntest-- > 0)
        sol();
}

Compilation message (stderr)

power.cpp: In function 'int main()':
power.cpp:59:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |         freopen(task ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
power.cpp:60:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen(task ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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