Graph/Max_Area_of_Island_dfs.cpp at main · git5v/Graph · GitHub

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class Solution {

    int maxarea = 0;
    void dfs(vector<vector<int>>& grid , int i, int j, int n ,int m,int &area)
    {
        if(i>=n or j>=m or i<0 or j<0 or grid[i][j] != 1 ) return ;

        grid[i][j] = 0 ;

        area++;
        dfs(grid,i-1,j,n,m,area);
        dfs(grid,i+1,j,n,m,area);
        dfs(grid,i,j-1,n,m,area);
        dfs(grid,i,j+1,n,m,area);
        maxarea = max( maxarea , area);

    }

public:
    int maxAreaOfIsland(vector<vector<int>>& grid) {

        int n = grid.size();
        int m = grid[0].size();

        int area = 0;

        for(int i =0 ;i < n ; i++)
        {
            for (int j=0;j < m ; j++)
            {
                  if(grid[i][j]==1)
                  {
                      area = 0;
                    dfs(grid,i,j,n,m,area);
                  }
            }
        }
        return maxarea;
    }
};