Question

您好我正在尝试用C ++编写程序，生成并打印0到999之间的20个随机数，并在不使用内置函数的情况下执行以下操作，查找并打印：最小值，最大值，平均值，中位数，标准差，方差。在第15个元素上进行二分查找。请帮我解释一下代码。

到目前为止，我已经完成了这么多＃包括＃包括 #include

df1 <- data.frame(TIME_ACTUAL_DEPART = c("1899-12-30 10:43:41",
          "1899-12-30 20:01:27", "1899-12-30 06:41:07",
          "1899-12-30 19:29:19", "1899-12-30 13:24:12",
           "1899-12-30 23:12:14"),
          stringsAsFactors=FALSE)

Answer 1

你有办法，你的代码不会做任何你想要的事情。但是，您提到您是初学者，因此我修复了您的代码并设置了如何开始的基本结构。我留下了关于我改变了什么以及你需要做什么的评论。话虽如此，我不知道你的意思＆＃34;对第15个元素进行二元搜索＆＃34;

#include <iostream>
#include <cstdlib>
#include <time.h>

using namespace std;

int ra()
{
    // You wanted a number between 0 and 999 inclusive so do not add 1
    // Instead do a modulus of 1000
    int r = rand() % 1000;
    return r;
}

int main ()
{
    // Do this to get different random numbers each time you run your program
    srand(time(NULL));

    // You have to call ra as a function. Do this by writing: ra()
    // Here I am storing 20 random numbers in an array
    int nums[20];
    for (unsigned int i = 0; i < 20; ++i)
    {
        nums[i] = ra();
        cout << "Index: " << i << ", random number: " <<  nums[i] << endl;
    }

    // Iterate to find the minimum number
    int minimum = nums[0];
    for (unsigned int i = 1; i < 20; ++i)
        if (nums[i] < minimum)
            minimum = nums[i];
    cout << "Minimum value: " << minimum << endl;

    // TODO: Find the maximum in basically the same way

    // TODO: Find the average by summing all numbers then dividing by 20

    // TODO: Find the median by sorting nums and taking the average of the two center elements

    // TODO: etc.

    return 0;
}

Answer 2

#include <iostream>
#include <cstdlib>
#include <ctime>
using namespace std;

int r;
int ra;
int i=0;

int ra(){

r = (rand() % 999) + 1;

return r;
}

int main ()
{
int random_;

srand((int)time(0));

while (i++ < 20)
{
    random_ = r;
    cout<< random_<<endl;
}

return 0;
}

使用函数在C ++中编写代码

2 个答案: