#include<stdio.h>
#include<stdlib.h>

int main()
{
	const float PI=3.14, Rterre=6378;           //déclarations
	float surface, volume, R, rapportsurface, rapportvolume, densite, masse;
	
	printf("radius de la planete en km?  ");        //demander l'informations du User
	scanf("%f",&R);
	
	printf("densité de la planete en tonnes*km-3?  ");
	scanf("%f",&densite);
	
	surface= 4.0 *PI* R*R;            //calculations
	volume= 4.0/3.0* PI* R*R*R;
	masse= densite*volume;
	
	rapportsurface= surface/(4.0*PI*Rterre*Rterre);
	rapportvolume= volume/(4.0/3.0*PI*R*R*R);
	
	printf("%s%f%s\n","\nsurface de la planete: ",surface," km2\n");         //communiquer l'info vers User
	printf("%s%f%s","volume de la planete: ",volume," km3\n\n");
	
	printf("%s%e%s","\nmasse de la planete:",masse,"tonnes\n\n");
	
	printf("%s%f%s\n","rapport de la surface de la planete a celle de la terre: ",rapportsurface,"\n");         //communiquer l'info vers User
	printf("%s%f%s","rapport du volume de la planete a celui de la terre: ",rapportvolume,"\n");
	
	//system("pause");            //arreter l'execution
	return 0;
}