diagonal difference hackerrank solution

In the diagonal difference challenge of hackerrank, the user is provided a square matrix of N*N size and the challenge is to calculate the absolute difference between the left to right diagonal and right to left diagonal. 

The part where I got stuck was finding the sum of the second diagonal. The sum of the first diagonal was easy. 

Also, I learned about the inbuilt absolute function of the language, this function will be used later to find the absolute difference between first and the second diagonal. Make sure to get the syntax of absolute function correct.   

Diagonal Difference challenge

Sample input 

3

11 2 4

4 5 6

10 8 -12

Sample Output

15

Explanation

The primary diagonal is:

11

   5

     -12

Sum across the primary diagonal: 11 + 5 – 12 = 4

The secondary diagonal is:

     4

   5

10

Sum across the secondary diagonal: 4 + 5 + 10 = 19

Difference: |4 – 19| = 15

Diagonal Difference HackerRank Solution in C

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() { 
int N , a[100][100];
scanf("%d",&N);
int i,j,d1=0,d2=0;
for(i=0;i<N;i++)
for(j=0;j<N;j++)
scanf("%d",&a[i][j]);
for(i=0;i<N;i++)
{ 
d1+=a[i][i];
d2+=a[i][N-1-i];
}
int b=abs(d1-d2);
printf("%d",b);
return 0;
}

Diagonal Difference HackerRank Solution in C++

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
int N; 
cin >> N; 
int i, j; 
int sumdiag1 = 0; 
int sumdiag2 = 0; 
for(i = 0; i < N; i++){
for(j = 0; j< N; j++)
{
int no; 
cin >> no; 
if(i == j)
sumdiag1 += no; 
if(i+j == N-1)
sumdiag2 += no; 
}
}
cout << abs(sumdiag1 - sumdiag2);
return 0;
}

 

Diagonal Difference HackerRank Solution in Java

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

public static void main(String[] args) {
int n;
Scanner in=new Scanner(System.in);
n=in.nextInt();
int a[][]=new int[n][n];
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
a[i][j]=in.nextInt();
}
}
int pd=0,npd=0;
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
if(j==i)
pd=pd+a[i][j];
}
}
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
if(i==n-j-1){
npd=npd+a[i][j];
}
}
}
int dif=npd-pd;
dif=Math.abs(dif);
System.out.println(dif);
}
}

Diagonal Difference HackerRank Solution in Python

n = input()
arr=[]
for _ in range(n):
temp = map(int,raw_input().split())
arr.append(temp)
s1,s2 = 0,0
for i in range(n):
s1 += arr[i][i]
s2 += arr[-i-1][i]
print abs(s1-s2)

Attempt Diagonal Difference HackerRank Challenge 

Challenge link : https://www.hackerrank.com/challenges/diagonal-difference/

Next Challenge – Diagonal Difference HackerRank Solution

Link: https://exploringbits.com/plus-minus-hackerrank-solution/