Home > Source Codes > Software Programs > C > String Programs > To check whether the given string is palindrome-method 2

To check whether the given string is palindrome-method 2

Thursday, December 4th, 2008

Here is  another program, advanced version of the previous program, to check if the entered string is a palindrome. Palindrome is a string segment, which reads same from both the directions. The same method is implemented here in the program also.

Logic :  The given string is referred by two names, where one is traced by the SOL (Start Of Line) and the other is traced from EOL (End Of Line). In every iteration, the condition is checked, if both the characters are the same. If so, sets a flag, “pal” as true (i.e. 1), and hence prints out the result.

The problem can also solved in another method, where we check  by reversing the string and then comparing.

#include<stdio.h>
#include<conio.h>
int stpal(char str[50]);
void main()
{
char str[50];
int pal;
clrscr();
printf(“nnt ENTER A STRING…: “);
gets(str);
pal = stpal(str);
if(pal)
printf(“nt THE ENTERED STRING IS A PALINDROME”);
else
printf(“nt THE ENTERED STRING IS NOT A PALINDROME”);
getch();
}
int stpal(char str[50])
{
int i = 0, len = 0, pal = 1;
while(str[len]!=’′)
len++;
len–;
for(i=0; i<len/2; i++)
{
if(str[i] == str[len-i])
pal = 1;
else
{
pal = 0;
break;
}
}
return pal;
}
Download exe and source code here.

Avatar Image

Author Name :
Ranjith

Total : 13 Comments

Simillar Posts

13 Responses to To check whether the given string is palindrome-method 2

  1. Bird
    October 10th, 2009 at 1:28 pm

    It works fine but it is case sensitive. How to solve that?

  2. Chetan
    January 17th, 2010 at 2:29 pm

    THIS THING ALSO WORKS !! EASILY UNDERSTANDABLE !!!

    #include
    #include
    int main()
    {
    int i,j,check=0;
    char str[100];

    printf(“ENTER A STRING:\n”);
    gets(str);
    for(j=0;str[j]!=”;j++);
    j=j-1;
    i=0;
    while(i<=j)
    {
    if(str[i]==str[j])
    {
    i=i+1;
    j=j-1;
    check=1;
    }
    else
    {
    check=0;
    break;
    }
    }

    if(check==1)
    printf("PALINDROME:");
    else
    printf("NOT A PALINDROME\n");

    getch();

    }

  3. lopa
    June 5th, 2010 at 11:47 am

    i couldnt understand ur 9th number line// for(j=0;str[j]!=”;j++);
    can u pls explain?

  4. noel
    August 2nd, 2010 at 10:59 pm

    i couldn’t understand the following part:
    for(j=0;str[j]!=” “;j++)
    j=j–;
    i=0

  5. priya
    January 24th, 2011 at 7:13 pm

    last program is working.easy to enderstand

  6. SUMI
    February 23rd, 2011 at 10:05 pm

    9TH LINE IS USED FOR CALCULATING THE LENGTH OF THE STRING..

  7. m
    July 14th, 2011 at 10:10 am

    Is it raptor compatible ???

  8. Mahesh kumar dewat
    September 4th, 2011 at 11:17 am

    #include
    #include
    #include
    void main(void)
    {
    int i,len,halflen,flag=1;
    char str[50];
    clrscr();
    printf(“Enter a string:\n”);
    gets(str);
    len=strlen(str);
    halflen=len/2;
    for(i=0;i<halflen;i++)
    {
    if(str[i]!=str[i+halflen])
    flag=0;
    break;

    }
    if(flag)
    printf("It is a Palindrome.");
    else
    printf("It is not a Palindrome.");
    getch();
    }

  9. Mahesh kumar dewat
    September 4th, 2011 at 11:18 am

    #include
    main()
    {
    char a[20],b[20];
    printf(“enter a string”);
    scanf(“%s”,&a);
    strcpy(b,a);//copies string a to b
    strrev(b);//reverses string b
    if(strcmp(a,b)==0)//compares if the original and reverse strings are same
    printf(“\n%s is a palindrome”,a);
    else
    printf(“\n%s is not a palindrome”,a);
    return 0;
    }

  10. pradeep
    November 8th, 2011 at 1:57 pm

    fuck u man u r wrong…………….both eg are wrong.

  11. deena
    December 2nd, 2011 at 12:19 pm

    definitely this will work…..thanks to mahesh kumar dewat.

    #include
    #include//this headel file is important
    main()
    {
    char a[20];
    char b[20];
    printf(“enter a string”);
    gets(a);
    strcpy(b,a);//copies string a to b
    strrev(b);//reverses string b
    if(strcmp(a,b)==0)//compares if the original and reverse strings are same
    printf(“\n%s is a palindrome”,a);
    else
    printf(“\n%s is not a palindrome”,a);
    return 0;
    }

  12. Kaushik
    December 4th, 2011 at 9:54 am

    You need to include the header file to get the desired output!#include
    #include
    #include
    main()
    {
    char a[20];
    char b[20];
    printf(“enter a string”);
    gets(a);
    strcpy(b,a);//copies string a to b
    strrev(b);//reverses string b
    if(strcmp(a,b)==0)//compares if the original and reverse strings are same
    printf(“\n%s is a palindrome”,a);
    else
    printf(“\n%s is not a palindrome”,a);
    return 0;
    }

  13. Ranjeet
    December 7th, 2011 at 11:32 am

    @ Kaushik

    #include
    #include

Leave a Reply

Question and Answer
C/C++ Unix & Linux Wordpress
Source codes
C C++ Java

Free email signup