A program to check if the string is palindrome with and without using Stack | Using C language | Data structure |

 🤔What is a palindrome?

• A palindrome is a word, number, phrase, or other sequences of characters that reads the same backward (from right to left) as forward (from left to right).
• For example: madam, 313, ABCCBA, 12321 etc.

👉Click here to Read about Stack and its push, pop and Other operations

👨‍💻Write a program to check if the string is palindrome using Stack.

CODE:

🔘With using Stack

   

    //using Stack

    #include<stdio.h>

    #include<string.h>

    main()

    {

        int tops1=-1,tops2=-1;

        int i,stringlength,flag=0;

        char S1[100],S2[100];

        printf("Enter the string:");

        gets(S2);

        // strcpy, strrev, strlen, etc. are the function of string.h header file.

        strcpy(S1,S2); //strcpy used for copy string S2 into string S1

        strrev(S2); //strrev used for reverse string S2

        stringlength=strlen(S1); //strlen used for calculate the length of string S1

        tops1=stringlength-1;

        tops2=stringlength-1;

        for(i=0;i<stringlength;i++)

        {

            if(S1[tops1]==S2[tops2])

            {

                tops1--;

                tops2--;

            }

        }

        if(tops1==-1 && tops2==-1)

        {

            printf("string is palindrom");

        }

        else

        {

            printf("string is not palindrom !!!");

        }

    }

👨‍💻Write a program to check if the string is palindrome without using Stack.

CODE:

🔘Without using Stack

   

    //without using Stack

    #include<stdio.h>

    #include<string.h>

    main()

    {

        char S1[100] ,S2[100];

        puts("Enter the string:");

        gets(S2);

            // strcpy, strrev, strlen, strcmp etc. are the function of string.h header file.

        strcpy(S1,S2); //strcpy used for copy string S2 into string S1

        strrev(S1); //strrev used for reverse string S2

        if(strcmp(S1,S2)==0) //strcmp used for compare two strings S1 and S2

        {

            printf("string is palindrom");

        }

        else

        {

            printf("string is not palindrom !!");

        }

    }

(Both codes produce the same output)

OUTPUT:

Note: C language is a case-sensitive language (which means 'A' does not equal 'a' )