C :

#include<stdio.h>
int main()
{
	double s[50];
	double t;
	int i;

	for (int j = 0; j < 3; j++)
	{
		scanf("%lf", &s[j]);
	}
	for (i = 0; i < 3; i++)
	{
		if (s[i-1] > s[i])
		{
			t = s[i-1];
			s[i-1] = s[i];
			s[i] = t;
		}
	}
	for (int j = 0; j < 3; j++)
	{
		printf("%.3lf ", s[j]);
	}
	printf("\n");
}

C++ :

#include <cstdio>
#include <cstdlib>
int swap(float &a,float &b){
  float t;
  if (a>b) { t=a;a=b;b=t;}
}
int main(){
float a, b, c, t;
  scanf("%f%f%f", &a, &b, &c);
  if(a > b) swap(a,b);
  if(a > c) swap(a,c);
  if(b > c) swap(b,c);
  printf("%.3f %.3f %.3f\n", a, b, c);
  //system("pause");
  return 0;
}

Pascal :

var max,a,b,c:real;
begin
readln(a,b,c);
max:=0;
if c<b then begin max:=b;b:=c;c:=max;end;
if b<a then begin max:=a;a:=b;b:=max;end;
if c<b then begin max:=b;b:=c;c:=max;end;
writeln(a:0:3,' ',b:0:3,' ',c:0:3);
end.