function diagonalDifference(arr) {
    let sum1=0,sum2=0,i,j,k,l,result;
    let n = arr.length - 1;
     k=n;
     for(l=0; l<arr.length; l++){
            sum1 = sum1 + arr[k][l];
            k--;  
        }
    for(i=0; i<arr.length; i++){
            sum2 = sum2 + arr[i][i];
        } 
        if(sum1>sum2){
            result = sum1 - sum2
        }else{
            result = sum2 - sum1
        }
        return result
}