<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<int> blue_dist(n, INT_MAX-1);
      vector<int> red_dist(n, INT_MAX-1);
      blue_dist[0] = red_dist[0] = 0;

      int count = n-1;
      while (count-- > 0){
        for (int i=0; i<=n-1; i++)
        {
          for (auto& r: redEdges){
            //if (r[0] == 0) red_dist[r[1]] = 1;
            if (r[1] == i) {
              if (blue_dist[r[0]] + 1 < red_dist[i]){
                red_dist[i] = blue_dist[r[0]] + 1;
              }
            }
          }

          for (auto& b: blueEdges){
            //if (b[0] == 0) blue_dist[b[1]] = 1;
            if (b[1] == i) {
              if (red_dist[b[0]] + 1 < blue_dist[i])
              {
                blue_dist[i] = red_dist[b[0]] + 1;
              }
            }
          }
        }
      }

      vector<int> ret(n, INT_MAX);
      ret[0] = 0;
      for (int i=1; i<ret.size(); i++){
        ret[i] = min(blue_dist[i], red_dist[i]);
        if (ret[i] == INT_MAX-1){
          ret[i] = -1;
        }
      }
      return ret;
    
    }
};
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