找到总和为 15 的最小数字对

Question

我试图找到最小的一对数字来实现 15 的总和。我正在为它们创建新数组并将该数组传递给添加该数组元素并生成真或假的方法。如果方法返回 false，数组大小将增加。

public class FindMinimum {

    static int arr[] = { 10, 3, 2, 13 };
    static int numArr[] = new int[30];
    static int arrLength = 2;
    static boolean status = false;
    static int number;

    public static void main(String args[]) {
        for (int i = 0; i < arrLength; i++) {
            numArr[i] = arr[i];
        }
        if (checkPair(numArr)) {
            System.out.println("Number found");
        } else {
            arrLength = arrLength + 1;
            System.out.println("Increasing array length by one");
        }
    }

    public static boolean checkPair(int x[]) {
        for (int i = 0; i < x.length; i++) {
            number = number + x[i];
        }
        if (number == 15) {
            status = true;
            for (int i : x) {
                System.out.println(i);
            }
        } else {
            status = false;
        }
        return status;
    }
}

预期结果是“13 ,2”的最小加法对

Answer 1

如果我理解正确需要找到总是加到 15 的最小对。如果这是正确的，下面的代码应该可以解决它。

public static void main(String args[]) {

        Arrays.sort(arr);
        for (int i=0,j=arr.length-1;i<arr.length && j>=0;) {
            if ((arr[i]+arr[j])<15) {
                /*System.out.println(arr[i]+"-"+arr[last-i]);
                break;*/
                i++;
            } else if ((arr[i]+arr[j])>15) {
                j--;
            } else {
                System.out.println(arr[i]+"-"+arr[j]);
                break;
            }
        }
    }

Answer 2

import java.util.Scanner;

public class FindMinimumPair {

    static Scanner sc = new Scanner(System.in);
    static int userArr[];
    static int numArr[]; // New array to take number / pairs from main array to compare with else numbers
                            // in the main array
    static int arrLength = 1; // increase the array length of numArr if pair is more than 2 numbers
    static boolean status = false; // check method returns true or false
    static int sum;

    public static void main(String args[]) {
        System.out.println("Sum of pair should be ?");
        sum = sc.nextInt();
        System.out.println("Enter the lenght of an array");
        int userArrLength = sc.nextInt();
        userArr = new int[userArrLength];
        System.out.println("Enter array integers upto " + userArrLength);

        for (int i = 0; i < userArrLength; i++) {
            userArr[i] = sc.nextInt();
        }

        // Loop to read numbers from main array
        for (int i = 0; i < userArr.length; i++) {
            // Defines the length of new array
            numArr = new int[arrLength]; // initialize the new array
            // Loop to add numbers into new array
            for (int j = 0; j < arrLength; j++) {
                numArr[j] = userArr[j]; // add numbers into new array
            }
            if (check(numArr)) { // call check method and pass new array in it
                for (int a : numArr) { // if returns true then print that array (contains the pair)
                    System.out.print(a + " ");
                }
                System.out.print(userArr[numArr.length]); // print the last number which is the part of numArr
                System.out.println(" is equals to " + sum);
            } else {
                System.out.println("Numbers not found");
            }
            arrLength = arrLength + 1; // increase the array length if false
        }
    }

    public static boolean check(int number[]) {
        int x = 0;
        // Loop to make sum of all numbers of numArr (make it single number)
        for (int j = 0; j < number.length; j++) {
            x = x + number[j];
        }

        outer: for (int i = 0; i < number.length; i++) { // loop for elements in numArr array

            for (int j = 0; j < userArr.length; j++) { // loop for given array elements
                if (x + userArr[j] == sum) { // check each number of given array with the sum of numArr
                    status = true;
                    break outer; // breaks outer loop and returns true
                } else {
                    status = false;
                }
            }
        }
        return status;
    }
}