Give reason for output 3.

Question

#include <iostream>
using namespace std;

int main() {
int arr[2][3]={{3,5,1},{2,9,4}};
int brr[2][3]={{2,5,8},{9,2,6}};
for(int i=0;i<2;i++){
for(int j=0;j<3;j++){

brr[i][j]+=arr[i][j];
}
}
cout<<brr[1][3];
return 0;
}

Answer 1

It was asked in a challenge in this app and the output is actually 3.
As I copied the code and had run this one

Answer 2

in the statement " cout<<brr[1][3];"
index is out of boundary. maybe you want to output brr[1][2] which is 10.