Reforma subtask.cpp

#include <bits/stdc++.h>
using namespace std;
const int maxn = 110;
vector<int> grafo[maxn];
vector<pair<int,int>> arestas;
int main(){
    ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
    int n, m;
    cin >> n >> m;
    for(int i=1; i<=m; i++){
        int u, v;
        cin >> u >> v;
        grafo[u].push_back(v);
        grafo[v].push_back(u);
    }
    for(int i=1; i<n; i++){
        for(int j=i+2; j<=n; j++){
            arestas.push_back({i, j});
        }
    }
    cout << arestas.size() << "\n";
    for(int i=0; i<arestas.size(); i++){
        pair<int,int> x = arestas[i];
        cout << x.first << " " << x.second << "\n";
    }
    return 0;
}