public static void main ( String args [ ] ) {
  Scanner s = new Scanner ( System . in ) ;
  int n = s . nextInt ( ) ;
  int arr [ ] = new int [ n ] ;
  int prefix [ ] = new int [ n ] ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    arr [ i ] = s . nextInt ( ) ;
  }
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    if ( i < 2 ) {
      prefix [ i ] = arr [ i ] ;
    }
    else {
      prefix [ i ] = prefix [ i - 2 ] + arr [ i ] ;
    }
  }
  int suffix [ ] = new int [ n ] ;
  for ( int i = n - 1 ;
  i >= 0 ;
  i -- ) {
    if ( i + 2 >= n ) {
      suffix [ i ] = arr [ i ] ;
    }
    else {
      suffix [ i ] = suffix [ i + 2 ] + arr [ i ] ;
    }
  }
  int count = 0 ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    int left = 0 , right = 0 ;
    if ( i > 0 ) {
      left = prefix [ i - 1 ] ;
    }
    if ( i + 2 < n ) {
      left += suffix [ i + 2 ] ;
    }
    if ( i > 1 ) {
      right = prefix [ i - 2 ] ;
    }
    if ( i + 1 < n ) {
      right += suffix [ i + 1 ] ;
    }
    if ( left == right ) {
      count ++ ;
    }
  }
  System . out . println ( count ) ;
}

public static void main ( String args [ ] ) { Scanner s = new Scanner ( System . in ) ; int n = s . nextInt ( ) ; int arr [ ] = new int [ n ] ; int prefix [ ] = new int [ n ] ; for ( int i = 0 ; i < n ; i ++ ) { arr [ i ] = s . nextInt ( ) ; } for ( int i = 0 ; i < n ; i ++ ) { if ( i < 2 ) { prefix [ i ] = arr [ i ] ; } else { prefix [ i ] = prefix [ i - 2 ] + arr [ i ] ; } } int suffix [ ] = new int [ n ] ; for ( int i = n - 1 ; i >= 0 ; i -- ) { if ( i + 2 >= n ) { suffix [ i ] = arr [ i ] ; } else { suffix [ i ] = suffix [ i + 2 ] + arr [ i ] ; } } int count = 0 ; for ( int i = 0 ; i < n ; i ++ ) { int left = 0 , right = 0 ; if ( i > 0 ) { left = prefix [ i - 1 ] ; } if ( i + 2 < n ) { left += suffix [ i + 2 ] ; } if ( i > 1 ) { right = prefix [ i - 2 ] ; } if ( i + 1 < n ) { right += suffix [ i + 1 ] ; } if ( left == right ) { count ++ ; } } System . out . println ( count ) ; }
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right: (identifier))) consequence: (block (expression_statement (update_expression (identifier))))))) (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (identifier))))))