C++：清除Dos窗口上的内容，让程序可以循环执行

C++：清除Dos窗口上的内容，让程序可以循环执行
当这个程序运行一次之后，窗口上就会出现很多信息，现在我想在不重新运行程序
的情况下清除上一次运行后在Dos窗口上出现的信息，然后接着做下一次的测试，请问代码该怎么改写？高手赐教！！！谢谢

代码：
// Program 6.7 Accessing characters in a string
#include <iostream>
#include <string>
#include <cctype>
#include <iomanip>
using std::cout;
using std::cin;
using std::endl;
using std::string;

int main() {
  string text;                               // Stores the input

  cout << endl <<"This program is used to count the number of occurrence of each digit in your input. "
  << endl<< endl<<"Please enter a line of text:" << endl<< endl<< endl;

  // Read a line of characters including spaces
  std::getline(cin, text);
  cout<< endl<< endl<< endl << "You entered:" << endl << endl<<  endl<<text << endl<< endl;
  int  count[10]= {0};
  for(int i = 0 ; i < text.length() ; i++) 
  if(std::isdigit(text[i]))                
      switch(text[i]) {        
        case '0': 
      count[0]++;
      break;
        case '1': 
      count[1]++;
      break;
    case '2': 
      count[2]++;
      break;
    case '3': 
      count[3]++;
      break;
    case '4': 
      count[4]++;
      break;
    case '5': 
      count[5]++;
      break;
    case '6': 
      count[6]++;
      break;
    case '7': 
      count[7]++;
      break;
    case '8': 
      count[8]++;
      break;
    case '9': 
      count[9]++;
      break;
                        
      }
  int sum=0;
  for(int i=0;i<10;i++)
  sum+=count[i];
  cout<< endl<< "Your input contained "<<sum<<" digits."<< endl<< endl
     <<"Below is a frequency table listing the different digits in ascending order with their frequencies and their relative frequencies."
     <<"\n"<<"\n"<<"\n"<<"\n";  
  cout<<"\t"<<"Digit"<<"\t\t"<<"Frequency"<<"\t"<<"Relative Frequency"<<"\n"<<"\n" ; 
  for(int i=0;i<10;i++)
     cout<< "       "<<"\t"
         <<i  <<"\t\t"<< count[i] << "\t\t"<< count[i]/static_cast<double>(sum)
       << endl;
 cout<< endl<< endl;


  return 0;
}

全部

M***

回答