java - 用户输入的数字不重复

Question

这个问题已经有答案了:

Non duplicates numbers in user input (5 个回答)

已关闭 3 年前。

通过这个彩票程序，我试图确保数字在 1-59 的范围内，相同的数字不能输入两次，并且只能输入数字。我唯一需要帮助的代码是唯一可以输入数字的部分。

public void choose() {
        System.out.println("\n");
        int temp;
        boolean valid;

        for (int i = 0; i < 6; i++) {
            do {
                valid = true;
                System.out.print("Enter in an integer from 1 to 59: ");
                temp = keyboard.nextInt();
                if (temp < 1 || temp > 59) {
                    System.out.println("Error, please enter a valid integer !!");
                    valid = false;
                }
                for (int j = 0; j < i; j++) {
                    if (numbers[j] == temp) {
                        System.out.println("Please enter a different number as you have already entered this !!");
                        valid = false;
                        break;
                    }
                }
                numbers[i] = temp;
            } while (!valid); 
        }
    }

Answer 1

按如下方式进行:

import java.util.Arrays;
import java.util.Scanner;

public class Main {
    static int[] numbers = new int[6];
    static Scanner keyboard = new Scanner(System.in);

    public static void main(String args[]) {
        // Test
        choose();
        System.out.println(Arrays.toString(numbers));
    }

    static void choose() {
        int temp = 0;
        boolean valid;
        for (int i = 0; i < 6; i++) {
            // Check if the integer is in the range of 1 to 59
            do {
                valid = true;
                System.out.print("Enter in an integer (from 1 to 59): ");
                try {
                    temp = Integer.parseInt(keyboard.nextLine());
                    if (temp < 1 || temp > 59) {
                        System.out.println("Error: Invalid integer.");
                        valid = false;
                    }
                } catch (NumberFormatException e) {
                    System.out.println("Error: The input is not an integer.");
                    valid = false;
                }
                for (int j = 0; j < i; j++) {
                    if (numbers[j] == temp) {
                        System.out.println("Please enter a different number as you have already entered this");
                        valid = false;
                        break;
                    }
                }
                numbers[i] = temp;
            } while (!valid); // Loop back if the integer is not in the range of 1 to 100
        }
    }
}

示例运行:

Enter in an integer (from 1 to 59): a
Error: The input is not an integer.
Enter in an integer (from 1 to 59): 12.23
Error: The input is not an integer.
Enter in an integer (from 1 to 59): 10
Enter in an integer (from 1 to 59): 200
Error: Invalid integer.
Enter in an integer (from 1 to 59): 20
Enter in an integer (from 1 to 59): 5
Enter in an integer (from 1 to 59): 10
Please enter a different number as you have already entered this
Enter in an integer (from 1 to 59): 20
Please enter a different number as you have already entered this
Enter in an integer (from 1 to 59): 6
Enter in an integer (from 1 to 59): 7
Enter in an integer (from 1 to 59): 12
[10, 20, 5, 6, 7, 12]