用C++实现分层抽样，总体为：50,50.3,49.8,49.9,47.6,47,47.5,43,43.2,43.3, 43.1,43.3,43,43.5,0。层数为4，抽样数为5,。输出抽样结果

要实现这种特定情况下的分层抽样，我们可以直接手动划分层次并计算每个层次的样本数量。给定的总体较小，可以直接列出每个层次的数据和对应的抽样数目。由于总共有16个样本，我们假设四个层次分别为小于等于43, 43.1到43.5, 44到47, 和大于47。以下是简单实现这个过程的C++代码：

#include <iostream>
#include <vector>
#include <random>

// 定义层次和抽样
std::vector<int> layers = {43, 43.1, 43.2, 43.3, 43.5, 44, 47, 47.6, 47.5, 49.8, 49.9, 50, 50.3};
int numSamplesPerLevel = 5;

// 划分层次
std::vector<std::vector<int>> divideIntoLayers(const std::vector<int>& data) {
    std::vector<std::vector<int>> layers;
    int start = 0, end = 0;
    while (end < data.size()) {
        // 找到每个层次的边界
        while (end + 1 < data.size() && data[end + 1] <= data[start]) {
            ++end;
        }
        // 创建新的层次并将数据添加进去
        layers.push_back(std::vector<int>(data.begin() + start, data.begin() + end + 1));
        start = end + 1;
    }
    return layers;
}

// 抽样
void stratifiedSampling(const std::vector<std::vector<int>>& layers, int numSamples) {
    for (size_t i = 0; i < layers.size(); ++i) {
        std::cout << "层次 " << i+1 << ": ";
        for (int j = 0; j < numSamples; ++j) {
            int index = rand() % layers[i].size();
            std::cout << layers[i][index] << " ";
        }
        std::cout << "\n";
    }
}

int main() {
    std::vector<int> data = {/* 给定的总体 */};
    std::vector<std::vector<int>> dividedLayers = divideIntoLayers(data);

    stratifiedSampling(dividedLayers, numSamplesPerLevel);
    return 0;
}