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C Program to Check if a given String is Palindrome



C Program to Check if a given String is Palindrome

This program accepts a string and checks whether a given string is palindrome.

- Take a string as input and store it in the array string[].
- Store the same string into the another array reverse_string[] in the reverse fashion.
- Using for loop compare the elements of both the arrays.
- If all the elements of the array are same, then it is a palindrome. Otherwise it is not a palindrome.

    #include <stdio.h>

    #include <string.h>

    void main()

    {

        char string[25], reverse_string[25] = {'\0'};

        int  j, length = 0, flag = 0;

        fflush(stdin);

        printf("Enter a string \n");

        gets(string);

        /*  keep going through each character of the string till its end */

        for (j = 0; string[j] != '\0'; j++)

        {

            length++;

        }

        for (j = length - 1; j >= 0; j--)

        {

           reverse_string[length - j - 1] = string[j];

        }

        /*

         * Compare the input string and its reverse. If both are equal

         * then the input string is palindrome.

         */

        for (j = 0; j < length; j++)

        {

            if (reverse_string[j] == string[j])

                flag = 1;

            else

                flag = 0;

        }

        if (flag == 1)

            printf("%s is a palindrome \n", string);

        else

            printf("%s is not a palindrome \n", string);

    }