+3 votes

Well, you know the value of PI, all you have to do is create either a variable or a macro for it.

#include <stdio.h> #define PI 3.14159265359f // float PI = 3.14159265359f; // This would work just as fine int main() { float y = PI * 4.0f; printf("y = %f\n", y); return 0; }

commented
Nov 19, 2021
by
YOU AINT A HACKERR MF
(100 points)

i agree with you since you declared the value of PI as a global var it can be used anywhere in the prorgram

+1 vote

You can also use it directly by adding another library in your code.

The library is **math.h**, I will demonstrate it by calculating area of a circle, so it would look like,

#include<stdio.h>

#include<math.h>

int main()

{

float r;

printf("Enter the value of radius of circle\n");

scanf("%f",&r);

printf("The area of the circle is %f\n",M_PI*r*r);

return 0;

}

Hope it helps

_{ }

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