package suanfa_shiyan;public class max_lianxu {public static long maxSubSum(int[] a, int left, int right) {// 如果子序列只有一个元素if (left == right) {// 该元素大于0时返回它if (a[left] > 0) {return a[left];} else { // 该元素小于或等于0时返回0return 0;}}int mid = (left + right) / 2; // 求中间位置long maxLeftSum = maxSubSum(a, left, mid); // 求左边的最大子序列和long maxRightSum = maxSubSum(a, mid + 1, right); // 求右边的最大子序列和想知道为什么这两步可以分别求出左右两边最大连续子列和// 计算横跨中间的最大子序列和long maxLeftBorderSum = 0, leftBorderSum = 0;for (int i = mid; i >= left; i--) { // 从中间向左遍历leftBorderSum += a[i]; // 逐渐增加和if (leftBorderSum > maxLeftBorderSum) {maxLeftBorderSum = leftBorderSum; // 更新左边界最大和}}long maxRightBorderSum = 0, rightBorderSum = 0;for (int j = mid + 1; j <= right; j++) { // 从中间向右遍历rightBorderSum += a[j]; // 逐渐增加和if (rightBorderSum > maxRightBorderSum) {maxRightBorderSum = rightBorderSum; // 更新右边界最大和}}// 返回三者中的最大值return Math.max(Math.max(maxLeftBorderSum, maxRightBorderSum),maxLeftBorderSum+maxRightBorderSum);}public static void main(String[] args) {int[] a = { -2, -2, -3, 6, -1, -1, 0, -5, 4 };long result = maxSubSum(a, 0, a.length - 1);System.out.println("The maximum subarray sum is: " + result); // 输出结果}}哪位大佬能帮忙解释一下吗
