C + + read function reads int shaping data _c language

Read function definition

The read function reads the data in a file to a certain length and stores it in a new array. Used to read data from a file.

Function prototype istream& read (char* s, streamsize N);

Parameter char* s The char type array pointer to the flow of the data, Streamsize n indicates the length of the array

#include <iostream>
using namespace std;
int read ()//read function body part
{
  int x=0,f=1;char ch=getchar ();
  while (ch< ' 0 ' | | Ch> ' 9 ')
  {
    if (ch== '-') f=-1;
    Ch=getchar ();
  }
  while (ch>= ' 0 ' &&ch<= ' 9 ')
  {
    x=x*10+ch-' 0 ';
    Ch=getchar ();
  }
  return x*f;
}
int main ()
{
  int n=read ()//This is read n (note that you can only read data of type int, long long also need to change)
  system ("pause");
  return 0;
}

Use example of the Read function

#include <iostream>//std::cout
#include <fstream>//std::ifstream

int main () {

std:: Ifstream is ("Test.txt", std::ifstream::binary);
if (IS) {
//Get length of File:
is.seekg (0, is.end);
int length = IS.TELLG ();
IS.SEEKG (0, Is.beg);

char * buffer = new char [length];

Std::cout << "Reading" << length << "Characters ... ";
Read data as a block:
Is.read (buffer,length);

if (IS)
std::cout << "All characters read successfully.";
else
std::cout << "error:only" << is.gcount () << "could be read";
Is.close ();

... buffer contains the entire file

... delete[] buffer;
return 0;
}