<p>You are given an integer <code>n</code>, the number of nodes in a directed graph where the nodes are labeled from <code>0</code> to <code>n - 1</code>. Each edge is red or blue in this graph, and there could be self-edges and parallel edges.</p>

<p>You are given two arrays <code>redEdges</code> and <code>blueEdges</code> where:</p>

<ul>
	<li><code>redEdges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is a directed red edge from node <code>a<sub>i</sub></code> to node <code>b<sub>i</sub></code> in the graph, and</li>
	<li><code>blueEdges[j] = [u<sub>j</sub>, v<sub>j</sub>]</code> indicates that there is a directed blue edge from node <code>u<sub>j</sub></code> to node <code>v<sub>j</sub></code> in the graph.</li>
</ul>

<p>Return an array <code>answer</code> of length <code>n</code>, where each <code>answer[x]</code> is the length of the shortest path from node <code>0</code> to node <code>x</code> such that the edge colors alternate along the path, or <code>-1</code> if such a path does not exist.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> n = 3, redEdges = [[0,1],[1,2]], blueEdges = []
<strong>Output:</strong> [0,1,-1]
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> n = 3, redEdges = [[0,1]], blueEdges = [[2,1]]
<strong>Output:</strong> [0,1,-1]
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= n &lt;= 100</code></li>
	<li><code>0 &lt;= redEdges.length,&nbsp;blueEdges.length &lt;= 400</code></li>
	<li><code>redEdges[i].length == blueEdges[j].length == 2</code></li>
	<li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub>, u<sub>j</sub>, v<sub>j</sub> &lt; n</code></li>
</ul>

class Solution {
public:
    vector<int> shortestAlternatingPaths(int n, vector<vector<int>>& redEdges, vector<vector<int>>& blueEdges) {
        vector<vector<pair<int,int>>> v(n);
        map<vector<int>,int> m;

        for(auto i : redEdges){
            v[i[0]].push_back({i[1],0});
        }

        for(auto i : blueEdges){
            v[i[0]].push_back({i[1],1});
        }  

        vector<int> dis(n,INT_MAX);
        dis[0] = 0;


        deque<vector<int>> q;
        q.push_back({0,0,-1});

      

        while(!q.empty()){

            auto z = q.front();
            q.pop_front();

            for(auto i : v[z[0]]){
                if(i.second != z[2] && m[{z[0] , i.first , i.second}] != 1 ){
                    dis[i.first] = min(1 + z[1] , dis[i.first] ) ;
                    m[{z[0] , i.first , i.second}] = 1 ;
                    q.push_back({i.first,1+z[1],i.second});
                }
            }

            
        }

        for(int i =0 ; i < n ; i++){
            if(dis[i] == INT_MAX) {
                dis[i] = -1 ; 
            }
        }

        return dis;

    }
};
22379