c
#include <stdio.h>
#define LOWER 0
#define UPPER 300
#define STEP  20
main(){
	int fahr;
	printf("Fahrenheit temperatures \t Celsius\n");
	for(fahr=UPPER; fahr >= LOWER; fahr -= STEP){
		
    printf("\t%3d \t\t\t%6.1f\n",fahr,(5.0 / 9.0) * (fahr -32));
	}
}
Hi'story