两个数组求和为一个固定数值的所有组合java实现

Question

如题所述

Answer 1

import java.util.Arrays;

/**
* 列举数组中任意元素和为定值的组合
*/
public class SolveProb {
// Arrays.sort(arr);
static int[] flag = new int[100];
static int index = 0;// 记录当前
public SolveProb() {
}
public static void numGroup(int[] arr, int start, int length, int sum) {
if (sum == 0) {
for (int j = 0; j < index; j++) {
System.out.print(flag[j]);
}
System.out.println();
} else {
for (int i = start; i < length; i++) {
flag[index++] = arr[i];
SolveProb.numGroup(arr, i + 1, length-1, sum - arr[i]);
}
}
index--;
}

public static void main(String[] args) {
int[] arr = { 1, 3, 2, 4, 5, 6, 7, 8, 9 };
Arrays.sort(arr);
int sum = 7;
SolveProb.numGroup(arr, 0, arr.length, sum);
}
}