Question

我的任务是

在C ++中，使用指针来计算用户输入的字符数。在屏幕上打印输出

这就是我所做的。我不知道如何计算输入的字符。

#include <iostream>

using namespace std;

int main()
{
    int string[20] = { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 };
    int sum = 0;
    char a;
    cout << "Enter less than 20 characters(no space) : ";
    for (int i = 0; i < 20; i++)
    {
        cin >> a;
        string[i] = a;
        if (string[i] != 0)
            sum = sum + 1;
        else
            break;
    }
    cout << endl;
    cout << "The number of characters in " << *string << " is " << sum;
    return 0;
}

Answer 1

根据我对要求的理解，您将需要使用一个指针。

int main()
{
  static const size_t MAX_CHARS = 20;
  char text[MAX_CHARS] = {0};
  std::cout << "Enter up to 20 characters, no spaces: ";
  size_t quantity;
  char c;
  while (std::cin >> c)
  {
     if (quantity >= MAX_CHARS) break;
     text[quantity++] = c;
  }
  // Count the characters using a pointer: 
  if (quantity < MAX_CHARS)
  {
     text[quantity] = '\0';
  }
  else
  {
     text[MAX_CHARS - 1] = '\0';
  } 
  quantity = 0;
  char * pointer = &text[0];
  while (*pointer != '\0')
  {
    ++quantity;
    ++pointer;
  }
  std::cout << "Characters entered: " << quantity << "\n";
  return 0;
}

我想这是理解指针的练习。

否则，我建议使用std::string和std::string::length()。

如何计算输入的字符数？

1 个答案: