识别,如果Java中存在重复的输入整数

Question

如何识别重复输入的整数,如果我输入1 1 2 3 4,它会说1号是重复的

import java.util.*;

public class Haha {

    static Scanner console = new Scanner(System.in);

    public static void main(String[] args) {

        int[] items = new int[5];
        int sum;

        System.out.println("Enter five integers: ");
        sum = 0;

        for (int counter = 0; counter < items.length; counter++) {
            items[counter] = console.nextInt();
            sum = sum + items[counter];
        }

        System.out.println("The sum of the numbers = " + sum);
        System.out.print("The numbers in the reverse" + "order are: ");

        for (int counter = items.length - 1; counter >= 0; counter--) {
            System.out.print(items[counter] + " ");
        }

        System.out.println();
    }
}

Answer 1

你需要的只是一个Set:)

    int[] arr = { 1, 1, 2, 3, 4,3 };
    Set<Integer> hs = new HashSet<Integer>();
    for (int i = 0; i < arr.length; i++) {
        boolean b = hs.add(arr[i]);  // add returns false if the value is already present in the set
        if (!b) {
            System.out.println("duplicate value is : " + arr[i]);
        }
    }

O/P:

duplicate value is : 1
duplicate value is : 3