Island Perimeter

https://leetcode.com/problems/island-perimeter/

 class Solution {
public:
    int islandPerimeter(vector<vector<int>>& grid) {
        int m=grid.size();//row
        int n=grid[0].size();//col
        int ans=0;
        for(int i=0;i<m;i++){
            for(int j=0;j<n;j++){
                if(grid[i][j]==1){
                    ans+=4;//if 1 in matrix perimeter 4
                    if(i<m-1 && grid[i+1][j]) ans--;//if neighbours are 1 we reduce ans
                    if(j<n-1 && grid[i][j+1]) ans--;
                    if(i && grid[i-1][j]) ans--;
                    if(j && grid[i][j-1]) ans--;
                }
                
            }
        }
        return ans;
    }
};

Comments

Post a Comment

Popular posts from this blog

Perfect Peak of Array

  Given an integer array A of size N . You need to check that whether there exist a element which is strictly greater than all the elements on left of it and strictly smaller than all the elements on right of it. If it exists return 1 else return 0 .  https://www.interviewbit.com/old/problems/perfect-peak-of-array/ int Solution::perfectPeak(vector<int> &A) { int ans=-1; int l[A.size()]; int r[A.size()]; l[0]=A[0]; r[A.size()-1]=A[A.size()-1]; for(int i=1;i<A.size();i++){     l[i] = max(A[i],l[i-1]); } for(int i=A.size()-2;i>=0;i--){     r[i] = min(A[i],r[i+1]); } for(int i=1;i<A.size()-1;i++){     if(A[i]>l[i-1]&&A[i]<r[i+1]){         return 1;     } } if(ans==-1){     return 0; } }  
Read more

Is Rectangle?

 https://www.interviewbit.com/old/problems/is-rectangle/ int Solution::solve(int A, int B, int C, int D) {      if (((A==B)&&(C==D))||((A==C)&&(B==D))||((A==D)&&(B==C))){         return 1;     }else{         return 0;     } }  
Read more

Sort array with squares!

 https://www.interviewbit.com/old/problems/sort-array-with-squares/      vector<int> Solution::solve(vector<int> &arr) {         int mid=0;     for(int i=0;i<arr.size();i++)     {         if(arr[i]>=0)         {             mid=i;             break;         }     }     int i=mid-1,j=mid;     vector<int>res(arr.size());     int k=0;     while(i>=0 && j<arr.size())     {         if((arr[i]*arr[i])<(arr[j]*arr[j]))         {             res...
Read more