public static void main ( String [ ] args ) {
  Scanner input = new Scanner ( System . in ) ;
  int test = input . nextInt ( ) ;
  while ( test -- > 0 ) {
    int n = input . nextInt ( ) , k = input . nextInt ( ) ;
    String s = input . next ( ) ;
    int count = 0 ;
    for ( int i = 0 ;
    i < ( n % 2 == 1 ? n / 2 : n / 2 - 1 ) ;
    i ++ ) {
      if ( s . charAt ( i ) == s . charAt ( n - 1 - i ) ) {
        count ++ ;
      }
      else {
        break ;
      }
    }
    if ( count >= k ) System . out . println ( "YES" ) ;
    else System . out . println ( "NO" ) ;
  }
}

public static void main ( String [ ] args ) { Scanner input = new Scanner ( System . in ) ; int test = input . nextInt ( ) ; while ( test -- > 0 ) { int n = input . nextInt ( ) , k = input . nextInt ( ) ; String s = input . next ( ) ; int count = 0 ; for ( int i = 0 ; i < ( n % 2 == 1 ? n / 2 : n / 2 - 1 ) ; i ++ ) { if ( s . charAt ( i ) == s . charAt ( n - 1 - i ) ) { count ++ ; } else { break ; } } if ( count >= k ) System . out . println ( " YES " ) ; else System . out . println ( " NO " ) ; } }
(method_declaration (modifiers) type: (void_type) name: (identifier) parameters: (formal_parameters (formal_parameter type: (array_type element: (type_identifier) dimensions: (dimensions)) name: (identifier))) body: (block (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (object_creation_expression type: (type_identifier) arguments: (argument_list (field_access object: (identifier) field: (identifier)))))) (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (while_statement condition: (parenthesized_expression (binary_expression left: (update_expression (identifier)) right: (decimal_integer_literal))) body: (block (local_variable_declaration type: (integral_type) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list))) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (local_variable_declaration type: (type_identifier) declarator: (variable_declarator name: (identifier) value: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list)))) (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: (parenthesized_expression (ternary_expression condition: (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (decimal_integer_literal)) consequence: (binary_expression left: (identifier) right: (decimal_integer_literal)) alternative: (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (decimal_integer_literal))))) update: (update_expression (identifier)) body: (block (if_statement condition: (parenthesized_expression (binary_expression left: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (identifier))) right: (method_invocation object: (identifier) name: (identifier) arguments: (argument_list (binary_expression left: (binary_expression left: (identifier) right: (decimal_integer_literal)) right: (identifier)))))) consequence: (block (expression_statement (update_expression (identifier)))) alternative: (block (break_statement))))) (if_statement condition: (parenthesized_expression (binary_expression left: (identifier) right: (identifier))) consequence: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal)))) alternative: (expression_statement (method_invocation object: (field_access object: (identifier) field: (identifier)) name: (identifier) arguments: (argument_list (string_literal)))))))))