# How to Find Area of circle using Pointers in C

In this article, we are going to learn How to Find Area of circle using Pointers in C with examples.The formula to calculate the area of a circle is ℼ*r2 where r is the radius of the Circle.

### C Program to find Area of Circle Using Pointers

In this example, we will write a C Program to find Area of Circle Using Pointers. We are asking the user to input the radius of the circle and we use it to find the area of a circle

```#include<stdio.h>
#define PI 3.14

int main()
{

Areaptr=&Area;

return 0;
}

```

Output

```Please enter the radius of Circle: 5
The Area of Cicle with radius 5.000 = 78.500
```

### 2. Find Area of Circle Using Pointer & Function in C language

In this example, we are modifying the above program and moving the area calculation logic to a separate function.
We will take the input radius from the user and then calculate the area in a function. This function will return the area by using a pointer.

```#include<stdio.h>
#define PI 3.14
int calculatearea(float *r, float *area);
int main()
{

Areaptr=&Area;

return 0;
}
int calculatearea(float *r, float *area)
{
*area = PI * *r * *r;
}
```

Output

```Please enter the radius of Circle: 5
The Area of Cicle with radius 5.000 = 78.500
```