НАЙ-ЗАПАЗЕНА ПЪТНА МРЕЖА

#include <iostream>
#include <vector>
#include <queue>
using namespace std;
#define MAXN 1000;
#define MAXM 1500;

int main() {
    vector<vector<int>> G;
    int res = 0;
    int gradove;
    int putishta;
    cin >> gradove;
    cin >> putishta;
    while (putishta > 0) {
        vector<int> g;
        int a;
        int b;
        cin >> a;
        cin >> b;
        g.push_back(a);
        g.push_back(b);
        G.push_back(g);
        putishta--;
    }
    for (int i = 0; i < G.size(); i++) {
        if (G[i][0] != 0) {
            int resultCount = 1;
            queue<int> que;
            que.push(G[i][0]);
            G[i][0] = 0;
            que.push(G[i][1]);
            G[i][1] = 0;
            while (que.size() > 0) {
                for (int j = i + 1; j < G.size(); j++) {
                    if (G[j][0] == que.front()) {
                        resultCount++;
                        que.push(G[j][1]);
                        G[j][0] = 0;
                        G[j][1] = 0;
                    }
                }
                for (int j = i + 1; j < G.size(); j++) {
                    if (G[j][1] == que.front()) {
                        resultCount++;
                        que.push(G[j][0]);
                        G[j][0] = 0;
                        G[j][1] = 0;
                    }
                }
                que.pop();
            }
            if (res < resultCount) {
                res = resultCount;
            }
        }
    }

    cout << res;
    system("Pause");

}