在c++里面 怎么把double型的保留三位小数输出？如100 ，6.2542.输出为100.000，6.254.

Question

如题所述

Answer 1

double a = 6.2542;
printf("%.3lf", a);

Answer 2

double a = 6.2542;
printf("%.3f", a);
double b = 100;
printf("%.3f", a);

Answer 3

#include<iostream>
#include<iomanip>

using namespace std;

int main()
{
float a=100,b=2.34422;
cout<<setiosflags(ios::fixed)<<setprecision(3);
cout<<a<<endl;
cout<<b<<endl;
printf("%.3f\n",a);
return 0;
}