Submission #497671

#	Time	Username	Problem	Language	Result	Execution time	Memory
497671		hgmhc	Cijanobakterije (COCI21_cijanobakterije)	C++17	70 / 70	51 ms	8404 KiB

Main

#include <bits/stdc++.h>
#define REP(i,a,b) for (auto i = (a); i <= (b); ++i)
#define SIZE(x) int(x.size())
#define debug(x) cerr << #x << " is " << x << endl
#define el '\n'
using namespace std; using ll = long long;

const int N = 1e5+3;
int n, m;
vector<int> adj[N];
vector<int> components;
bool visited[N];

void dfs(int s) {
    if (visited[s]) return;
    visited[s] = true;
    for (auto u : adj[s]) {
        dfs(u);
    }
}

void dfs1(int &x, int &l, int s = 1, int e = 0, int d = 0) {
    if (l < d) {
        x = s;
        l = d;
    }
    for (auto u : adj[s]) if (u != e) {
        dfs1(x,l,u,s,d+1);
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> m;
    REP(i,1,m) {
        int u, v; cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    REP(i,1,n) {
        if (not visited[i]) {
            components.push_back(i);
            dfs(i);
        }
    }
    int answer = 0;
    for (auto s : components) {
        int x = s, l = 0;
        dfs1(x,l,s);
        dfs1(x,l = 0,x);
        answer += l+1;
    }
    cout << answer;
}

• Subtask 1: 15 / 15
• Subtask 2: 6 / 6
• Subtask 3: 6 / 6
• Subtask 4: 15 / 15
• Subtask 5: 28 / 28