text: This function adds A [ ] [ ] and B [ ] [ ] , and stores the result in C [ ] [ ]
code: function add ( A , B , C ) { let i , j ; for ( i = 0 ; i < N ; i ++ ) for ( j = 0 ; j < N ; j ++ ) C [ i ] [ j ] = A [ i ] [ j ] + B [ i ] [ j ] ; }