Create 200-NumberOfIslands.cpp

Author: DionysiosB

200-NumberOfIslands.cpp

@@ -0,0 +1,32 @@
+class Solution {
+public:
+
+    void dfs(std::vector<std::vector<char>>& grid, int row, int col){
+        if(row < 0 || row >= grid.size()){return;}
+        if(col < 0 || col >= grid[0].size()){return;}
+        if(grid[row][col] != '1'){return;}
+        grid[row][col] = 'x';
+        dfs(grid, row - 1, col);
+        dfs(grid, row + 1, col);
+        dfs(grid, row, col - 1);
+        dfs(grid, row, col + 1);
+    }
+
+    int numIslands(vector<vector<char>>& grid) {
+
+        int nr = grid.size();
+        int nc = grid[0].size();
+        int cnt(0);
+
+        for(int row = 0; row < nr; row++){
+            for(int col = 0; col < nc; col++){
+                if(grid[row][col] == '1'){
+                    ++cnt;
+                    dfs(grid, row, col);
+                }
+            }
+        }
+
+        return cnt;
+    }
+};