llrint(x)函数详解

long long int llrint(data_type x);

#include <iostream>  
#include<math.h>  
#include<cfenv>  
using namespace std;  
int main()  
{  
   float x=5.3;  
   std::cout << "Value of x is :" << x<<std::endl;  
   fesetround(FE_UPWARD);  
   cout<<"Rounded value of x is :"<<llrint(x);  
    return 0;  
}  

#include <iostream>  
#include<math.h>  
#include<cfenv>  
using namespace std;  
int main()  
{  
   double x=7.9;  
   std::cout << "Value of x is :" << x<<std::endl;  
   fesetround(FE_DOWNWARD);  
   cout<<"Rounded value of x is :"<<llrint(x);  
    return 0;  
}