Exercise 3.42 (Deitel: C How to Program 6th Edition)

Write a program that reads the radius of a circle (as a float value) and computes and prints the diameter, the circumference and the area. Use the value 3.14159 for π.

C Program: 

#include <stdio.h>
 
int main(){
    float jari, diameter, keliling, luas;
    printf("Masukan jari-jari: ");
    scanf("%f", &jari);
    diameter = 2*jari;
    keliling = 3.14159*2*jari;
    luas = 3.14159*jari*jari;
    printf("Diameter\t: %.2f\n", diameter);
    printf("Keliling\t: %.2f\n", keliling);
    printf("Luas\t: %.2f\n", luas);
    system("pause");
    return 0;
}

Output: