class Solution {
    public int[] sortedSquares(int[] arr) {
        for(int i = 0; i < arr.length; i  ){
            for(int j=i 1;j<arr.length;j  ){
                arr[i]=arr[i]*arr[i];
                arr[j]=arr[j]*arr[j];
                if(arr[j]<arr[i]){
                    int temp=0;
                    temp=arr[i];
                    arr[i]=arr[j];
                    arr[j]=temp;
                    
                    
                }
            }
        }
        return arr;
}
}

can you tell me where am going wrong.. for input [-4,-1,0,3,10] output should be [0,1,9,16,100] , My current output is [0,1,43046721,0,1874919424] .. I don't want to use Array.sort() . Wanted to write own code.. can you help me in fixing this and where am going wrong. Thanks in advance

CodePudding user response：

Your sort loop is functional but you are squaring each entry 4 times in a cumulative manner. One approach is to first square all the elements and then sort.

From your results you can see evidence:

(((3^2)^2)^2)^2 = 43046721

The second 0 is interesting:

(((-4^2)^2)^2)^2 = 4,294,967,296

which for a 32-bit int becomes 0.

And for 10:

(((10^2)^2)^2)^2 = 10,000,000,000,000,000

rolls over to 187491924.

So your code can simply be updated by first squaring the entries and then sort:

public int[] sortedSquares(int[] arr) {
    for (int i = 0; i < arr.length; i  ) {
        arr[i] = arr[i] * arr[i];
    }
    for(int i = 0; i < arr.length; i  ){
        for(int j=i 1;j<arr.length;j  ){
            if(arr[j]<arr[i]){
                int temp=0;
                temp=arr[i];
                arr[i]=arr[j];
                arr[j]=temp;
            }
        }
    }
    return arr;
}