Tuesday 10 March 2015

How to learn c programs of palindrome numbers


Given number is Palindrome or Not In C

Palindrome number in C

When we reversed any number. that the reverse number is equal to the actual number that is called palindrome

A number is called palindrome number if it is remain same when its digits are reversed. For example 121 is palindrome number. When we will reverse its digit it will remain same number i.e. 121

Palindrome numbers examples: 11, 22, 33, 44, 55, 66, 77, 88, 99, 101, 111, 121, 131, 141, 151, 161, 171, 181, 191 etc.

1. C program to find whether a number is palindrome or not

#include<stdio.h>
int main()
{
    int num,r,sum=0,temp;

    printf("Enter a number: ");
    scanf("%d",&num);

    temp=num;
    while(num)
    {
         r=num%10;
         num=num/10;
         sum=sum*10+r;
    }
    if(temp==sum)
         printf("%d is a palindrome",temp);
    else
         printf("%d is not a palindrome",temp);

    return 0;
}

Sample output:
Enter a number: 131
131 is a palindrome



2. find palindrome number in an range


#include<stdio.h>
int main()
{
    int num,r,sum,temp;
    int min,max;

    printf("Enter the minimum range: ");
    scanf("%d",&min);

    printf("Enter the maximum range: ");
    scanf("%d",&max);

    printf("Palindrome numbers in given range are: ");
    for(num=min;num<=max;num++)
    {
         temp=num;
         sum=0;

         while(temp)
         {
             r=temp%10;
             temp=temp/10;
             sum=sum*10+r;
         }
         if(num==sum)
             printf("%d ",num);
    }
    return 0;
}


Sample output:
Enter the minimum range: 1
Enter the maximum range: 50
Palindrome numbers in given range are: 1 2 3 4 5 6 7 8 9 11 22 33 44



3. How to check if a number is a palindrome using for loop

#include<stdio.h>
int main()
{
    int num,r,sum=0,temp;

    printf("Enter a number: ");
    scanf("%d",&num);

    for(temp=num;num!=0;num=num/10)
    {
         r=num%10;
         sum=sum*10+r;
    }
    if(temp==sum)
         printf("%d is a palindrome",temp);
    else
         printf("%d is not a palindrome",temp);

    return 0;
}

Sample output:
Enter a number: 1221
1221 is a palindrome



4. Check if a number is palindrome using recursion

#include<stdio.h>
int checkPalindrome(int);
int main()
{
    int num,sum;

    printf("Enter a number: ");
    scanf("%d",&num);

    sum = checkPalindrome(num);

    if(num==sum)
         printf("%d is a palindrome",num);
    else
    printf("%d is not a palindrome",num);

    return 0;
}

int checkPalindrome(int num)
{

    static int sum=0,r;

    if(num!=0)
    {
         r=num%10;
         sum=sum*10+r;
         checkPalindrome(num/10);
    }

    return sum;
}

Sample output:
Enter a number: 25
25 is not a palindrome