Basics and Common C Programs Part 2

Today I have posted programs to check prime number,program to find
GCD,LCM ,Sum of digit of a given number and How to write program
for Fibonacci Series in C language.
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1. /*How To Check whether a number is prime or not in C*/

#include<stdio.h>
#include<conio.h>
//Header files required are declared

void main()
{
//Beginning Of main()
int i=2,n,f=0;// Required variables are declared and initialized
clrscr();//Output Screen cleared

printf("Enter The Number To Test :\n");
scanf("%d",&n);
if(n==0 || n==1)
printf("%d is not prime no.",n);
else
{
while(i<n)
{
if(n%i==0)
{
f=1;
break;
}
i++;
}
if(f==0)
printf("%d is a prime number.",n);
else
printf("%d is not a prime number.",n);
       }
getch();
}//End Of main()


2./*How To To find the GCD of two numbers in C */

#include <stdio.h>
#include <conio.h>
//Header files required are declared

void main()
{
//Beginning Of main()
int a,b,c,i,x;// Required variables are declared
clrscr();//Output Screen cleared

puts("Enter the two numbers : ");
scanf("%d%d",&a,&b);
      printf("\nGCD of %d and %d is : ",a,b);
if(a<b)
{
c=a;
a=b;
b=c;
}
while(b>0)
{
c=a%b;
a=a/b;
a=b;
b=c;
}
printf("%d\n",a);
getch();
}//End Of main()


3./*How To Find out the LCM of two numbers in C*/

#include <stdio.h>
#include <conio.h>
//Header files required are declared

void main()
{
//Beginning Of main()
int a,b,c,i,x;// Required variables are declared
clrscr();//Output Screen cleared

puts("Enter the two numbers : ");
scanf("%d%d",&a,&b);

if(a<b)
{
c=a;
a=b;
b=c;
}

x=a*b;

for(i=a;i<x;i++)
{
if(i%a==0 && i%b==0)
break;
}

printf("\nLCM of %d and %d is : %d \n",b,a,i);
getch();
}//End Of main()

4./*How To  Calculate the sum of digit of a number*/

#include<stdio.h>
#include<conio.h>
//Required header files are declared
void main()
{
//Beginning Of main()
int d,m,n,s=0;// Required variables are declared
clrscr();

printf("Enter The Number To Find Sum Of Digits : \n");
scanf("%d",&n);

m=n;
while(n>0)
{//Sum Of digits calculated
d=n%10;
s=s+d;
n=n/10;
}

printf("Sum Of  Digits Of %d  Is : %d.\n",m,s);
getch();
}//End Of main()


5./*How to write program for Fibonacci Series : 0 1 1 2 3 5 8 13 ..
.....nth term*/

#include <stdio.h>
#include <conio.h>
//Header files required are declared

void fibo(int n)
{//Beginning of function fibo()
int i,a=1,b=0,c;
printf("0 ");
for(i=1;i<=n;i++)
      {//Loop to calculate and print the fibonacci series
c=a+b;
printf("%d ",c);
a=b;
b=c;
}
}//End of function fibo()

void main()
{
//Beginning Of function main()
int n;
clrscr();
printf("\nEnter The Term : ");
scanf("%d",&n);
fibo(n);
getch();
}//End of function main()

Related Basics and Common C Programs Part 3