제출 #1287014

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1287014		vahagng	Cijanobakterije (COCI21_cijanobakterije)	C++20	70 / 70	36 ms	11296 KiB

Main

//----------vahagng----------//
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
using namespace std;
// using namespace __gnu_pbds;

// template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif

void print(long long t) { cerr << t; }
void print(int t) { cerr << t; }
void print(string t) { cerr << t; }
void print(char t) { cerr << t; }
void print(double t) { cerr << t; }
void print(long double t) { cerr << t; }
void print(unsigned long long t) { cerr << t; }

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(T v[], V n) { cerr << "["; for (int i = 0; i < n; i++) { cerr << v[i] << " "; } cerr << "]"; }
template <class T, class V> void print(pair <T, V> p) { cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}"; }
template <class T> void print(vector <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T> void print(set <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T> void print(multiset <T> v) { cerr << "[ "; for (T i : v) { print(i); cerr << " "; } cerr << "]"; }
template <class T, class V> void print(map <T, V> v) { cerr << "[ "; for (auto i : v) { print(i); cerr << " "; } cerr << "]"; }

#define ll long long
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define ld long double
#define sz(v) v.size()
#define endl '\n'

const ll inf = 2e18, mod = 1e9 + 7, mod2 = 998244353;

void SetIO(string str = "") {
    if (str != "") {
        freopen((str + ".in").c_str(), "r", stdin);
        freopen((str + ".out").c_str(), "w", stdout);
    }
    else {
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    }
}

void FastIO() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
}

const int N = 2e5 + 10, M = 1e7 + 10;
const double eps = 1e-7;

mt19937 rnd(chrono::system_clock::now().time_since_epoch().count());

ll binpow(ll a, ll b, ll m) {
    ll res = 1;
    while (b) {
        if (b & 1) {
            res = (res * a) % m;
        }
        b >>= 1;
        a = (a * a) % m;
    }
    return res;
}

int n, m;
vector<int>adj[N];
pair<int,int>max_dist;
int dists[N], par[N];
bool visited[N];

void dfs(int node, int parent, int dist) {
    dists[node] = max(dists[node], dist);
    visited[node] = 1;
    par[node] = parent;
	if(dist > max_dist.first) {
		max_dist = {dist, node};
	}
	for(auto i: adj[node]) {
		if(i == parent) continue;
		dfs(i, node, dist + 1);
	}
}
 
pair<int, int> get_farthest_distance(int node) {
	max_dist = {-1, -1};
	dfs(node, -1, 1);
	return max_dist;
}

void solve(int tc) {
    cin >> n >> m;
    for(int i = 0; i < m; i++){
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    ll ans = 0;
    for(int i = 1; i <= n; i++){
        if(visited[i]) continue;
        auto mx = get_farthest_distance(i);
        mx = get_farthest_distance(mx.second);
        ans += mx.first;
    }
    cout << ans << endl;
}


void precalc() {
    
}

int main() {
    // SetIO("teamwork");
    FastIO();
    int test_case = 1;
    // cin >> test_case;
    precalc();
    int cnt = 1;
    while (test_case--) {
        solve(cnt++);
    }
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'void SetIO(std::string)':
Main.cpp:47:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |         freopen((str + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:48:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |         freopen((str + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:52:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   52 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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