How to find circle area using πr ² formula in C

πr² is a common formula to us.But can you find a circle area value by C?
if not,try this.It's help you to know how to find/print the value of a circle 
area in C programming language.


Code to print the value:


#include<stdio.h>
#define PI 3.1416

int main()
{
    float circle_area, r;

    printf("Enter the value of radius: \n");
    scanf("%f", &r);

    circle_area = PI *r * r;

    printf("The circle area is: %.2f\n", circle_area);


return 0;

}


OR,


#include<stdio.h>


int main()
{
    float circle_area, r, PI=3.1416;

    printf("Enter the value of radius: \n");
    scanf("%f", &r);

    circle_area = PI * r * r;

    printf("The circle area is: %.2f\n", circle_area);


return 0;

}

The Output is:

Face problems?No problem.You can share your problems by commenting below.or you can leave a massage us.Thank you.

make a currency converter By C programming language

We can make a simple currency converter by C programming language.

Lets see the code:

#include <stdio.h>
double convert(void);
int main(void){

    double taka;

    taka=convert();
    printf("In taka= %0.2lf\n",taka);

    return 0;
}

double convert(void)
{
    double dollars,multi_value;
    multi_value=80.0;

    printf("enter dollar amount: \n");
    scanf("%lf", &dollars);

    return dollars*multi_value;

}

Output:

It is really great.But if you face any problem or have any question,please comment below.

How to make simple calculator by C

We are going to make a simple calculator by C.By this calculator we can do summation,subtraction,multiplication and division.Lets have a look to the program.

#include <stdio.h>
#include <conio.h>

int main()
{
    float a,b,sum,sub,mul,div;
    char ch;

    printf("Enter a number: \n");
    scanf("%f", &a);

    printf("Enter another number: \n");
    scanf("%f", &b);

    sum=a+b;
    sub=a-b;
    mul=a*b;
    div=a/b;

    printf("What do you want?\n");
    printf("a: summation.\t b: subtraction.\nc: multiplication.\t d: division.\n");

    scanf(" %c",&ch);

    if(ch == 'a')
    {

        printf("summation value: %.2f\n",sum);

    }
    else if(ch == 'b')
    {

        printf("subtraction value: %.2f\n",sub);

    }
       else if(ch == 'c')
    {

        printf("multiplication value: %.2f\n",mul);

    }
       else if(ch == 'd')
    {

        printf("division value: %.2f\n",div);

    }
    else
    {

        printf("something went wrong!!\n");
    }

    return 0;
    }


Now Try it by yourself.If you face any problem and you have any question regarding the program you can comment below.
Thank you.

Summation,Subtraction,Multiplication and Division by C

Now we are going to do summation with C.Write down the following program and compile it.Then see what happen.

Program Code

#include <stdio.h>

int main ()

{

    int a;

    int b;

    int sum;

    a = 50;

    b = 60;

    sum = a + b;

    printf("sum is %d",sum);

    return 0;

}

Program details:

At first we named three variables as our wish.I took a,b, and sum.Here i assigned 50 for a and 60 for b.sum= a+b means i assigned a value in sum which is equal to a+b.You already know about the printf function.Here it commanded to print the value of sum.

Work for you:

Now you have to do subtraction,multiplication and division following this program.When you done post your program in comment box here or in our facebook group Coder Mania BD.

## If you face any problem with C program join our facebook group C Clinic by Coder Mania BD to get solution.

Thanks for being with Coder Mania BD.

DATA TYPE,VARIABLES,INPUT AND OUTPUT

DATATYPE: C has five types of basic Data.such as int,double,float,char and void.Today we are going to learn int Type data programming.int stand for integer.Integers are 0,1,2,3......

VARIABLES: A variable is nothing but a name given to a storage area that our programs can manipulate. Each variable in C has a specific type, which determines the size and layout of the variable's memory; the range of values that can be stored within that memory; and the set of operations that can be applied to the variable.

The name of a variable can be composed of letters, digits, and the underscore character. It must begin with either a letter or an underscore.Upper and lowercase letters are distinct because C is case-sensitive.

Now write this program on your compiler:

code:

           #include <stdio.h>

           int main()

           {

               int x,y;

               x = 5;

               y = 6;

               printf("%d",x);

           return 0;

           }

Output: 5

Description of the program: Here i wrote int x,y;. int stand for integer and here i declared two variables x & y.You can declare many variables.You can not write variables like 1x,$a,#x,+y,show-ans etc.You can use this operators or signs or numbers (1,$,+,#) after characters.And you can use show_ans.
In printf function i used "%d" for showing integer which i mentioned after it.

Can you do summation,subtraction,multiplication and division by C?See in my next post.
Thanks for being with coder mania BD.