Runtime: 75 ms (Top 80.5%) | Memory: 96.50 MB (Top 55.46%)

Author: AnasImloul

scripts/algorithms/I/Island Perimeter/Island Perimeter.cpp

@@ -1,63 +1,23 @@
-////**  hindi me samjho ab// 
-// agar mje left or right or bottom or top me 1 mila to me aaga badunga agar nahi
-//mila mtlb ya to wo boundary  hai  uske baad 0  ara hai agar esa hai to cnt+=1 
-//kardo kuki wo hi to meri boundary banegi . note : agar boundary hai mtlb 
-//i <0 or j<0 or i>=n or j>=m to cnt+=1 kardo or agar box ke side walo me 0 hai to wahan bhi cnt+=1 . 
-// hope it make sense 
-// please upvote if you like my post 
+// Runtime: 75 ms (Top 80.5%) | Memory: 96.50 MB (Top 55.46%)
+
 class Solution {
 public:
-     int cnt =0 ;
-bool vis[101][101] ;
-    bool valid( int i , int j, int n , int m){
-        if(i>=n or j>=m or i<0 or j<0 )
-             return false;
-        return true ;
-    }
     int islandPerimeter(vector<vector<int>>& grid) {
-        memset(vis,false , sizeof(vis)) ;
-        for(int i = 0 ; i <grid.size() ; i ++){ 
-              for(int  j=0 ; j<grid[0].size() ; j++) {
-                   
-                  
-                   if(grid[i][j]==1){
-                       
-                     solve(grid, i,j) ;
-                       return cnt ;
-                   }
-              }        
-         }
-        return 69;
+        int ans = 0 , row = grid.size(), col = grid[0].size();    
+        for(int i = 0 ; i < row ; i++)
+        {
+           for(int j = 0 ; j < col ; j++)
+           {
+               if( grid[i][j])
+               {
+                  ans+=4;
+                  if(i < row - 1 && grid[i+1][j])ans--; 
+                  if(j < col -1 && grid[i][j+1])ans--; 
+                  if(j  && grid[i][j-1])ans--; 
+                  if(i  && grid[i-1][j])ans--; 
+               }
+           } 
+        }
+        return ans;
     }
- void  solve(vector<vector<int>>&grid, int i , int j ){
-       int n = grid.size() ; 
-     int m = grid[0].size() ;
- vis[i][j]=true ;
-     if(!valid(i-1,j,n,m) or (valid(i-1,j,n,m) and grid[i-1][j]==0)){
-         cnt++ ;
-     }
-     else if(valid(i-1,j,n,m)and !vis[i-1][j])
-         solve(grid, i-1,j) ;
-     
-     if(!valid(i+1,j,n,m) or (valid(i+1,j,n,m) and grid[i+1][j]==0)){
-         cnt++ ;
-     }
-        else if(valid(i+1,j,n,m)and !vis[i+1][j])
-         solve(grid,i+1,j) ;
-     
-     if(!valid(i,j-1,n,m) or (valid(i,j-1,n,m) and grid[i][j-1]==0)){
-         cnt++ ;
-     }
-          else if(valid(i,j-1,n,m)and !vis[i][j-1])
-         solve(grid,i,j-1) ;
-     
-     if(!valid(i,j+1,n,m) or (valid(i,j+1,n,m) and grid[i][j+1]==0)){
-         cnt++ ;
-     }
-          else if(valid(i,j+1,n,m)and !vis[i][j+1])
-         solve(grid,i,j+1) ;
-     
-     
-     
-}
 };