static int minOperations ( int n , String a , String b , String c ) {
  int ans = 0 ;
  for ( int i = 0 ;
  i < n ;
  i ++ ) {
    char x = a . charAt ( i ) ;
    char y = b . charAt ( i ) ;
    char z = c . charAt ( i ) ;
    if ( x == y && y == z ) ;
    else if ( x == y || y == z || x == z ) {
      ans ++ ;
    }
    else {
      ans += 2 ;
    }
  }
  return ans ;
}

static int minOperations ( int n , String a , String b , String c ) { int ans = 0 ; for ( int i = 0 ; i < n ; i ++ ) { char x = a . charAt ( i ) ; char y = b . charAt ( i ) ; char z = c . charAt ( i ) ; if ( x == y && y == z ) ; else if ( x == y || y == z || x == z ) { ans ++ ; } else { ans += 2 ; } } return ans ; }
(method_declaration (modifiers) type: (integral_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (integral_type) name: (identifier)) (formal_parameter type: (type_identifier) name: (identifier)) (formal_parameter type: (type_identifier) name: (identifier)) (formal_parameter type: (type_identifier) name: (identifier))) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) (for_statement init: (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (decimal_integer_literal))) condition: (binary_expression left: (identifier) right: (identifier)) update: (update_expression (identifier)) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))))) (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (binary_expression left: (identifier) right: (identifier)))) alternative: (if_statement condition: (parenthesized_expression (binary_expression left: (binary_expression left: (binary_expression left: (identifier) right: (identifier)) right: (binary_expression left: (identifier) right: (identifier))) right: (binary_expression left: (identifier) right: (identifier)))) consequence: (block (expression_statement (update_expression (identifier)))) alternative: (block (expression_statement (assignment_expression left: (identifier) right: (decimal_integer_literal)))))))) (return_statement (identifier))))