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

\\Errors:
\\'n' was not declared in this scope
\\ expected ')' before ',' token
\\ expected unqualified-id before 'int'
void abst_diff(int arr[][n], int n){
int sum_1=0;
int sum_2=0;

for(int a_i = 0; a_i < n; a_i++)
    sum_1 = sum_1 + a[a_i][a_i];

for(int a_i = 0, a_j = n-1; a_i < n; a_i++, a_j--)
    sum_2 = sum_2 + a[a_i][a_j];

sum_2=abs(sum_2-sum_1);
cout << sum_2;

}

int main(){
int n;
cin >> n;
int arr[n][n];
for(int a_i = 0;a_i < n;a_i++){
   for(int a_j = 0;a_j < n;a_j++){
      cin >> arr[a_i][a_j];
   }
}
abst_diff(arr,n);
return 0;
}

```

Can someone please help me identify the error here in this code. its a fairly simple logic. the errors that i'm getting are for the line:
 void abst\_diff(int arr[][n], int n){