My c++ solution:

int diagonalDifference(vector> arr) { int diag1 = 0; int diag2 = 0; for(int i = 0; i

for(int i = 0; i<arr.size(); i++){
    for(int j = 0; j<arr.size(); j++){
        if(i+j==arr.size()-1){
            diag2 += arr[i][j];
        }else{
            continue;
        }
    }
}
int diff = diag2 - diag1;
if(diag2 - diag1 <0){
    return -(diff);
}else{
    return diff;
}

}