Submission #1266277

#	Time	Username	Problem	Language	Result	Execution time	Memory
1266277		Bui_Quoc_Cuong	Making Friends on Joitter is Fun (JOI20_joitter2)	C++20	1 / 100	494 ms	604 KiB

joitter2

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 300005;
int n, m;
namespace sub1 {
	bitset <55> e[55];
	void solve() {
		int ans = 0;
		while (m--) {
			int u, v; cin >> u >> v;
			if (e[u][v] == 0) {
				ans++;
				e[u][v] = 1;
			}
			while (1) {
				bool add = 0;
				for (int x = 1; x <= n; x++) {
					for (int y = 1; y <= n; y++) if (x != y && e[x][y]) {
						for (int z = 1; z <= n; z++) if (z != x && z != y) {
							if (e[y][z] && e[z][y] && e[x][z] == 0) {
								e[x][z] = 1;
								add = 1;
								ans++;
							} 
						}
					}
				}
				if (add == 0) break;
			}			
			cout << ans << "\n";
		}
	}			
}
namespace sub2 {
	vector <int> gout[2005], gin[2005];
	bitset <2005> e[2005];

	void solve() {		
		while (m--) {
			int u, v; cin >> u >> v;
			e[u][v] = 1;
			int ans = 0;

			gin[u].push_back(v);
			gout[v].push_back(u);

			queue <pair <int, int>> que;
			que.push({u, v});

			while (!que.empty()) {
				int u = que.front().first, v = que.front().second;
				que.pop();
				if (e[u][v] && e[v][u]) {
					for (int x = 1; x <= n; x++) if (x != u && x != v) {
						if (e[x][v] && e[x][u] == 0) {
							e[x][u] = 1;
							que.push({x, u});
						}
						if (e[x][u] && e[x][v] == 0) {
							e[x][v] = 1;
							que.push({x, v});
						}
					}
				}
			}

			for (int i = 1; i <= n; i++) ans+= e[i].count();
			cout << ans << "\n";
		}
	}
}
int32_t main(){
    ios_base::sync_with_stdio(0); cin.tie(0); 
    #define koa "kieuoanh"
    if(fopen(koa".inp", "r")){
        freopen(koa".inp", "r", stdin); freopen(koa".out", "w", stdout);
    }
    cin >> n >> m;
    if (n <= 50) {
    	return sub1::solve(), 0;
    }
    if (n <= 2000) {
    	return sub2::solve(), 0;
    }
    return 0;
}

Compilation message (stderr)

joitter2.cpp: In function 'int32_t main()':
joitter2.cpp:76:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |         freopen(koa".inp", "r", stdin); freopen(koa".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
joitter2.cpp:76:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   76 |         freopen(koa".inp", "r", stdin); freopen(koa".out", "w", stdout);
      |                                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 0 / 16
• Subtask 3: 0 / 83