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

class Solution {
public:
    bool isBipartite(std::vector<std::vector<int>>& graph) {
        int n = graph.size();
        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 (auto& v : graph[u]) {
                    if (color[v] == color[u]) {
                        return false;
                    }
                    if (color[v] == 0) {
                        q.push(v);
                    }
                    color[v] = -color[u];
                }
            }
        }
        
        return true;
    }
};