C :

#include <stdio.h>

int main(void) {
	double a, b, c;
	scanf("%lf%lf", &a, &b);
	c = a - b;
	printf("%.2lf\n", c);
	return 0; 
}

C++ :

#include<cstdio>
using namespace std;
int main()
{
	double a,b,s;
	scanf("%lf%lf",&a,&b);
	s=a-b;
	printf("%.2lf\n",s);
	return 0;
}

Pascal :

program ygj288;
  var
    a,b,c:real;
  begin
    read(a,b);
    c:=a-b;
    write(c:0:2);
  end.