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#include <iostream>
#include <vector>
#include <queue>

class Solution {
public:
    bool possibleBipartition(int n, std::vector<std::vector<int>>& dislikes) {
        std::vector<std::vector<int>> adj(n);
        for (auto& e : dislikes) {
            adj[e[0] - 1].push_back(e[1] - 1);
            adj[e[1] - 1].push_back(e[0] - 1);
        }
        
        std::vector<int> color(n, 0);
        std::queue<int> q;
        for (int i = 0; i < n; ++i) {
            if (color[i] != 0) {
                continue;
            }
            
            color[i] = 1;
            q.push(i);
            while (!q.empty()) {
                int u = q.front();
                q.pop();
                for (int& v : adj[u]) {
                    if (color[v] == 0) {
                        color[v] = -color[u];
                        q.push(v);
                    }
                    else if (color[u] == color[v]) {
                        return false;
                    }
                }
            }
        }
        
        return true;
    }
};