#include
int main()
{
double n,x,y;
scanf("%lf %lf %lf",&n,&x,&y);
printf("%lf,%lf,%lf",n,x,y);
return 0;
}
2.12
3.2145
2.134569
2.120000,3.214500,2.134569
2.12
3.2145
2.134569
2.12,3.2145,2.134569
//把%lf换成%g
#include<stdio.h>
int main()
{
double n,x,y;
scanf("%lf %lf %lf",&n,&x,&y);
printf("%g,%g,%g",n,x,y);
return 0;
}
printf("%#f",…)
用%g试试吧