<p>Given a 2D array of characters <code>grid</code> of size <code>m x n</code>, you need to find if there exists any cycle consisting of the <strong>same value</strong> in <code>grid</code>.</p>

<p>A cycle is a path of <strong>length 4 or more</strong> in the grid that starts and ends at the same cell. From a given cell, you can move to one of the cells adjacent to it - in one of the four directions (up, down, left, or right), if it has the <strong>same value</strong> of the current cell.</p>

<p>Also, you cannot move to the cell that you visited in your last move. For example, the cycle <code>(1, 1) -&gt; (1, 2) -&gt; (1, 1)</code> is invalid because from <code>(1, 2)</code> we visited <code>(1, 1)</code> which was the last visited cell.</p>

<p>Return <code>true</code> if any cycle of the same value exists in <code>grid</code>, otherwise, return <code>false</code>.</p>

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

<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2020/07/15/1.png" style="width: 231px; height: 152px;" /></strong></p>

<pre>
<strong>Input:</strong> grid = [[&quot;a&quot;,&quot;a&quot;,&quot;a&quot;,&quot;a&quot;],[&quot;a&quot;,&quot;b&quot;,&quot;b&quot;,&quot;a&quot;],[&quot;a&quot;,&quot;b&quot;,&quot;b&quot;,&quot;a&quot;],[&quot;a&quot;,&quot;a&quot;,&quot;a&quot;,&quot;a&quot;]]
<strong>Output:</strong> true
<strong>Explanation: </strong>There are two valid cycles shown in different colors in the image below:
<img alt="" src="https://assets.leetcode.com/uploads/2020/07/15/11.png" style="width: 225px; height: 163px;" />
</pre>

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

<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2020/07/15/22.png" style="width: 236px; height: 154px;" /></strong></p>

<pre>
<strong>Input:</strong> grid = [[&quot;c&quot;,&quot;c&quot;,&quot;c&quot;,&quot;a&quot;],[&quot;c&quot;,&quot;d&quot;,&quot;c&quot;,&quot;c&quot;],[&quot;c&quot;,&quot;c&quot;,&quot;e&quot;,&quot;c&quot;],[&quot;f&quot;,&quot;c&quot;,&quot;c&quot;,&quot;c&quot;]]
<strong>Output:</strong> true
<strong>Explanation: </strong>There is only one valid cycle highlighted in the image below:
<img alt="" src="https://assets.leetcode.com/uploads/2020/07/15/2.png" style="width: 229px; height: 157px;" />
</pre>

<p><strong class="example">Example 3:</strong></p>

<p><strong><img alt="" src="https://assets.leetcode.com/uploads/2020/07/15/3.png" style="width: 183px; height: 120px;" /></strong></p>

<pre>
<strong>Input:</strong> grid = [[&quot;a&quot;,&quot;b&quot;,&quot;b&quot;],[&quot;b&quot;,&quot;z&quot;,&quot;b&quot;],[&quot;b&quot;,&quot;b&quot;,&quot;a&quot;]]
<strong>Output:</strong> false
</pre>

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

<ul>
	<li><code>m == grid.length</code></li>
	<li><code>n == grid[i].length</code></li>
	<li><code>1 &lt;= m, n &lt;= 500</code></li>
	<li><code>grid</code> consists only of lowercase English letters.</li>
</ul>

class Solution {
public:
vector<vector<bool>> visited;
vector<vector<pair<int, int>>> parent;
bool bfs(int r, int c, vector<vector<char>>& grid){
    queue<pair<int, int>> q;
    q.push({r,c});
    visited[r][c]=true;
    parent[r][c]={-1,-1};
    pair<int, int> temp;
    int tempRow;
    int tempCol;
    while(!q.empty()){
        temp=q.front();
        q.pop();
        tempRow=temp.first;
        tempCol=temp.second;
        //Up
        if(tempRow>=1 && grid[tempRow-1][tempCol]==grid[tempRow][tempCol]){
            if(!visited[tempRow-1][tempCol]){
                visited[tempRow-1][tempCol]=true;
                parent[tempRow-1][tempCol]={tempRow, tempCol};
                q.push({tempRow-1, tempCol});
            }else if(parent[tempRow][tempCol].first != tempRow-1 || parent[tempRow][tempCol].second != tempCol) return true;
        }
        //Left
        if(tempCol>=1 && grid[tempRow][tempCol-1]==grid[tempRow][tempCol]){
            if(!visited[tempRow][tempCol-1]){
                visited[tempRow][tempCol-1]=true;
                parent[tempRow][tempCol-1]={tempRow, tempCol};
                q.push({tempRow, tempCol-1});
            }else if(parent[tempRow][tempCol].first != tempRow || parent[tempRow][tempCol].second != tempCol-1) return true;
        }
        //Down
        if(tempRow+1<grid.size() && grid[tempRow+1][tempCol]==grid[tempRow][tempCol]){
            if(!visited[tempRow+1][tempCol]){
                visited[tempRow+1][tempCol]=true;
                parent[tempRow+1][tempCol]={tempRow, tempCol};
                q.push({tempRow+1, tempCol});
            }else if(parent[tempRow][tempCol].first != tempRow+1 || parent[tempRow][tempCol].second != tempCol) return true;
        }
        //Right
        if(tempCol+1<grid[0].size() && grid[tempRow][tempCol+1]==grid[tempRow][tempCol]){
            if(!visited[tempRow][tempCol+1]){
                visited[tempRow][tempCol+1]=true;
                parent[tempRow][tempCol+1]={tempRow, tempCol};
                q.push({tempRow, tempCol+1});
            }else if(parent[tempRow][tempCol].first != tempRow || parent[tempRow][tempCol].second != tempCol+1) return true;
        }
    }
    return false;
}
    bool containsCycle(vector<vector<char>>& grid) {
        visited.resize(grid.size(), vector<bool>(grid[0].size(), false));
    parent.resize(grid.size(), vector<pair<int, int>>(grid[0].size()));
    for(int i=0;i<grid.size();i++){
        for(int j=0;j<grid[0].size();j++){
            if(visited[i][j]==false) {
                if (bfs(i, j, grid)) {
                    return true;
                }
            }
        }
    }
    return false;
    }
};
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