function diagonalDifference(arr) {
    // Write your code here
    let leftToRight = 0
    let rightToLeft = 0
for(let i =0;i<arr.length ;i++){
    leftToRight +=arr[i][i]
    rightToLeft += arr[i][arr.length-1-i]
}
return  Math.abs(leftToRight-rightToLeft)
}

def diagonalDifference(arr):
    # Write your code here
    ld=rd=0
    for i in range(n):
        ld+=arr[i][i]
        rd+=arr[i][n-1-i]
    if ld > rd:
        return ld - rd
    else:
        return rd - ld

def diagonalDifference(arr):
    n = len(arr)
    
    ld = rd = 0
    
    for i in range(n):
        ld += arr[i][i]
    for i in range(n):
        rd += arr[i][n-1-i]
       
    return abs(ld - rd)

n = int(input())

arr = []
for a in range(n):
    arr.append(list(map(int, input().split())))

result = diagonalDifference(arr)

print(result)

public static int diagonalDifference(List<List<Integer>> arr) {
        int d1 = 0;
        int d2 = 0;
        for(int index = 0; arr.size() > index; index++) {
            d1 += arr.get(index).get(index);
            d2 += arr.get(index).get(arr.size() - 1 - index);
        }
        return Math.abs(d1 - d2);
        
    }