问题：array1,array2为两个有序的升序数组，将array1和array2合并为一个升序有序数组
1.合并两个有序数组array1,array2，借助数组array3。从头开始，将array1的第一个元素和array2的第一个元素比较，小的放到array3中。
#include<stdio.h>#define MAX 15//合并两个有序数组a,b，借助数组cvoid MergeArray(int array1[], int len1, int array2[], int len2, int array3[], int len3){ if (len3 < len1 + len2) return; int index1 = 0, index2 = 0, index3 = 0; while (index1 < len1&&index2 < len2) { if (array1[index1] < array2[index2]) { array3[index3++] = array1[index1++]; } else { array3[index3++] = array2[index2++]; } } while (index1 < len1) { array3[index3++] = array1[index1++]; } while (index2 < len2) { array3[index3++] = array2[index2++]; } return;}int main(){ int array1[] = { 1,3,5,7,9 }; int array2[] = { 2,4,6,8,9 }; int len1 = sizeof(array1) / sizeof(int); int len2 = sizeof(array2) / sizeof(int); int array3[MAX]; MergeArray(array1, len1, array2, len2, array3, MAX); for (int i = 0; i < len1 + len2; i++) { printf("%d ", array3[i]); }}2.假设array1足够大，能够放下array1和array2，从后往前比较array1，和array2，大的元素放到最右边。
#include<stdio.h>#define MAX 15//合并两个有序数组array1,array2,从后往前比较，将array1和array2最后一个元素比较，大的放到len1+len2-1void MergeArray(int array1[], int len1, int array2[], int len2){ int index1 = len1 - 1; int index2 = len2 - 1; int index = len1 + len2 - 1; while (index1 >= 0&&index2 >= 0) { if (array1[index1] > array2[index2]) { array1[index--] = array1[index1--]; } else { array1[index--] = array2[index2--]; } } while (index1 >= 0) { array1[index--] = array1[index1--]; } while (index2 >= 0) { array1[index--] = array2[index2--]; } return;}int main(){ int array1[MAX] = {1,3,5,7,9,10 }; int array2[] = { 2,4,6,8,9 }; int len2 = sizeof(array2) / sizeof(int); MergeArray(array1, 6, array2, len2); for (int i = 0; i < 6 + len2; i++) { printf("%d ", array1[i]); }}