f0405.cpp

it is a usefull thing

//=====================================
// f0405.cpp
// 显式转换
//=====================================
#include<iostream>
#include<cmath>
using namespace std;
//-------------------------------------
int main(){
  double d = sqrt(123456.0);
  int a = static_cast<int>(d) * 8 + 5;
  int b = d * 8 + 5;
  cout<<d<<endl<<a<<endl<<b<<endl;
  a = 2000000000;
  b = 1000000000;
  int c = (static_cast<double>(a) + b)/2;
  cout<<a+b<<endl<<c<<endl;
}//====================================