/*
    Try This 3-2

    An improved Help system that uses a
    do-while to process a menu selection.
*/
class Help2 {
  public static void main(String args[])
    throws java.io.IOException {
    char choice, ignore;

    do {
      System.out.println("Help on:");
      System.out.println("  1. if");
      System.out.println("  2. switch");
      System.out.println("  3. for");
      System.out.println("  4. while");
      System.out.println("  5. do-while\n");
      System.out.print("Choose one: ");

      choice = (char) System.in.read();

      do {
        ignore = (char) System.in.read();
      } while(ignore != '\n');
    } while( choice < '1' | choice > '5');

    System.out.println("\n");

    switch(choice) {
      case '1':
        System.out.println("The if:\n");
        System.out.println("if(condition) statement;");
        System.out.println("else statement;");
        break;
      case '2':
        System.out.println("The switch:\n");
        System.out.println("switch(expression) {");
        System.out.println("  case constant:");
        System.out.println("    statement sequence");
        System.out.println("    break;");
        System.out.println("  // ...");
        System.out.println("}");
        break;
      case '3':
        System.out.println("The for:\n");
        System.out.print("for(init; condition; iteration)");
        System.out.println(" statement;");
        break;
      case '4':
        System.out.println("The while:\n");
        System.out.println("while(condition) statement;");
        break;
      case '5':
        System.out.println("The do-while:\n");
        System.out.println("do {");
        System.out.println("  statement;");
        System.out.println("} while (condition);");
        break;
    }
  }
}