数组递归折半求和

public class Main {public static int fun(int[] a, int begin, int end){if(begin != end){return fun(a, begin, (begin + end)/2) +  fun(a, (begin + end)/2 + 1, end);}return a[end];}public static void main(String[] args) {int[] a = {1, 2, 3, 4, 5, 6, 7, 8};int sum = fun(a, 0, 7);System.out.println(sum);}}