请用c++写一个合并函数，把两个升序排列的数组合并为一个升序数组。用随机数生成两个不等长有序数组测试合并函数。请用数组和vector类实现

使用数组实现：

#include <stdio.h>

void merge(int arr1[], int n1, int arr2[], int n2, int merged[]) {
    int i = 0, j = 0, k = 0;
    while (i < n1 && j < n2) {
        if (arr1[i] <= arr2[j]) {
            merged[k++] = arr1[i++];
        } else {
            merged[k++] = arr2[j++];
        }
    }
    while (i < n1) {
        merged[k++] = arr1[i++];
    }
    while (j < n2) {
        merged[k++] = arr2[j++];
    }
}

int main() {
    int arr1[] = {1, 3, 5, 7, 9};
    int arr2[] = {2, 4, 6, 8};
    int n1 = sizeof(arr1) / sizeof(arr1[0]);
    int n2 = sizeof(arr2) / sizeof(arr2[0]);
    int merged[n1 + n2];
    merge(arr1, n1, arr2, n2, merged);
    for (int i = 0; i < n1 + n2; i++) {
        printf("%d ", merged[i]);
    }
    printf("\n");
    return 0;
}

使用vector类实现：

#include <stdio.h>
#include <vector>

void merge(std::vector<int>& vec1, std::vector<int>& vec2, std::vector<int>& merged) {
    int i = 0, j = 0;
    while (i < vec1.size() && j < vec2.size()) {
        if (vec1[i] <= vec2[j]) {
            merged.push_back(vec1[i++]);
        } else {
            merged.push_back(vec2[j++]);
        }
    }
    while (i < vec1.size()) {
        merged.push_back(vec1[i++]);
    }
    while (j < vec2.size()) {
        merged.push_back(vec2[j++]);
    }
}

int main() {
    std::vector<int> vec1 = {1, 3, 5, 7, 9};
    std::vector<int> vec2 = {2, 4, 6, 8};
    std::vector<int> merged;
    merge(vec1, vec2, merged);
    for (int i = 0; i < merged.size(); i++) {
        printf("%d ", merged[i]);
    }
    printf("\n");
    return 0;
}

以上代码都是合并两个已经升序排列的数组，如果要合并多个数组，可以先将多个数组合并成两个数组，再使用以上代码合并两个数组。