C :

#include<stdio.h>
int main()
{
	double f,c;
	scanf("%lf",&f);
	c=5*(f-32)/9;
	printf("c=%.2f\n",c);
	return 0;
}

C++ :

#include<stdio.h>
int main()
{
    float f;
    scanf("%f",&f);
    printf("c=%.2f",5.0/9.0*(f-32));
    return 0;
}