Create 1020. Number of Enclaves 7 Apr (#141)

Author: Chayandas07

1020. Number of Enclaves 7 Apr

@@ -0,0 +1,49 @@
+class Solution {
+public:
+    bool ok(vector<vector<int>>& grid , int i , int j , int n , int m){
+        return (i >= 0 && i < n && j >= 0 && j < m && grid[i][j] != 0);
+    }
+    void dfs(vector<vector<int>>& grid, int i , int j , int n , int m , int & cnt){
+        if(!ok(grid , i , j , n , m)){
+            return ;
+        }
+        if(grid[i][j] == 1){
+            cnt++;
+        }
+        grid[i][j] = 0;
+        dfs(grid , i + 1 , j , n , m , cnt);
+        dfs(grid , i - 1 , j , n , m , cnt);
+        dfs(grid , i , j + 1 , n , m , cnt);
+        dfs(grid , i , j - 1 , n , m , cnt);
+    }
+    int numEnclaves(vector<vector<int>>& grid) {
+        int n = grid.size();
+        int m = grid[0].size();
+        int val = 0;
+        for(int i = 0 ; i < m ; i++){
+            if(grid[0][i] == 1){
+                dfs(grid , 0 , i , n , m , val);
+            }
+            if(grid[n-1][i] == 1){
+                dfs(grid , n-1 , i , n , m , val);
+            }
+        }
+        for(int i = 0 ; i < n ; i++){
+            if(grid[i][0] == 1){
+                dfs(grid , i , 0 , n , m , val);
+            }
+            if(grid[i][m-1] == 1){
+                dfs(grid , i , m-1 , n , m , val);
+            }
+        }
+        int cnt = 0;
+        for(int i = 0 ; i < n ; i++){
+            for(int j = 0 ; j < m ; j++){
+                if(grid[i][j] == 1){
+                    dfs(grid , i , j , n , m , cnt);
+                }
+            }
+        }
+        return cnt;
+    }
+};