JAVA:实现ThreeSum三数和问题算法(附完整源码)

package com.thealgorithms.others;

import java.util.Arrays;
import java.util.Scanner;
class ThreeSum {

    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt(); // Length of an array

        int a[] = new int[n];

        for (int i = 0; i < n; i++) {
            a[i] = sc.nextInt();
        }
        System.out.println("Target");
        int n_find = sc.nextInt();

        Arrays.sort(a); // Sort the array if array is not sorted

        for (int i = 0; i < n; i++) {

            int l = i + 1, r = n - 1;

            while (l < r) {
                if (a[i] + a[l] + a[r] == n_find) {
                    System.out.println(a[i] + " " + a[l] + " " + a[r]);
                    break;
                } // if you want all the triplets write l++;r--; insted of break;
                else if (a[i] + a[l] + a[r] < n_find) {
                    l++;
                } else {
                    r--;
                }
            }
        }

        sc.close();
    }
}

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