小编J-e*_*L-o的帖子

我通过翻阅我的C++书并重新编写C中的问题来教自己C.我想知道在C中声明变量常量的正确的行业标准方法.你还在main之外使用#define指令,还是可以使用main中的C++样式const int？

尝试编译一个包含5个选项的简单switch语句.1-4产生计算和输出,而#5退出程序.我做了一个do/while循环,所以如果输入选项5,程序将结束.我收到一个错误:

4_19.c: In function ‘main’:
4_19.c:95: error: ‘choice’ undeclared (first use in this function)
4_19.c:95: error: (Each undeclared identifier is reported only once
4_19.c:95: error: for each function it appears in.)

我不知道为什么它说它未宣布,因为我在开始时宣布它.我做错了什么？感谢名单.这是我的代码:

    /* C++ book. 4_19 The speed of sound in gases. 
Create a menu to choose between 4 gases. User then enters number of seconds
it took to travel to destination. The program will calculate how far the source was (from speed that is unique to gas density). Validate …

我是一名计算机科学专业的学生并参加了我的第一个C++课程.我有一个问题,了解我的代码发生了什么:

// This program uses the address of each element in the array. 
#include <iostream>
using namespace std;

int main()
{
    const int NUM_COINS = 5;
    int coins[NUM_COINS] = {5, 1, 25, 5, 10};
    int *p1;        // Pointer to a double.
    int count;                      // Counter variable. 

    // Use the pointer to display the values in the array. 
    cout << "Here are the values in the coins array: \n";
    for(count = 0; count << NUM_COINS; count++)
    {
        // Get the address …

我正在学习C++,需要帮助我的代码.我不明白我的第二个函数中是如何得到编译器错误的.它几乎是第一个镜像,但我没有从第一个得到任何错误.

#include <iostream>
using namespace std;

// Function prototypes
int getLargest(int[], int);
int getSmallest(int[],int);

int main()
{
    const int ARRAY_SIZE = 10;
    int array[ARRAY_SIZE];
    int count = 0;

    cout << "Please enter 10 numbers into the array.\n\n";
    for (count; count < ARRAY_SIZE; count++)
    {
        cout << "Number " << (count +1) << ": " ;
        cin     >> array[count];
    }

    // Call function to calculate largest number. 
    int largest = getLargest(array, ARRAY_SIZE);

    // Display the largest number
    cout << "The largest …