C++ read函数读入int整形数据

#include<iostream>using namespace std;int read()//read函数主体部分{  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()//这就是读入了n（注意只能用来读入int类型的数据，long long还需更改）  system("pause");  return 0;}

#include <iostream> // std::cout#include <fstream> // std::ifstreamint 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.";elsestd::cout << "error: only " << is.gcount() << " could be read";is.close();// ...buffer contains the entire file...delete[] buffer;}return 0;}