need help in pointers in C

[lucky1020]

hi friends,
i am new to this can any one help me regarding this issue
my aim is to Write a program which computes the largest palindrome substring of a string using pointers

Input: The input is the string whose largest palindrome substring should be found.

Output: The output displays the largest palindrome substring.

Sample Input:

Enter the string: Habitat

Sample Output:

The longest palindrome substring of Habitat is: tat
----------------------------------------------------------------------------------------------------------------
i am able to write the code with out using pointers can any one help me regarding this how can i write this using pointers

code with out pointers is

#include<stdio.h>
#include<conio.h>
#include<string.h>
main()
{
 char s[20],x[20],y[10],t[10];
 int i,j,l,k,l1=0;
 printf("Enter the string");
 gets(s);
 l=strlen(s);
 s[l]='\0';
 for(i=0;i<l;i++)
 {
   j=0;
   x[j]=s[i];         //taking the first character into X
   j++;
   x[j]='\0';
   for(k=i+1;k<l;k++)
    {
      x[j]=s[k];     
      j++;
      x[j]='\0';
      strcpy(t,x);
    if(strcmp(t,strrev(x))==0) //comparing the substring as if palindrome  
       {
     if(l1<strlen(x))  //if palindrome compare the length wih previous paindrome
     {
       strcpy(y,t);
       puts(y);          //print the longer palindrome
       l1=strlen(y);
     }
    }
 
    strrev(x);
      }
 
   }
 getch();
 }

[Meetee]

hi friends,
i am new to this can any one help me regarding this issue
my aim is to Write a program which computes the largest palindrome substring of a string using pointers

Input: The input is the string whose largest palindrome substring should be found.

Output: The output displays the largest palindrome substring.

Sample Input:

Enter the string: Habitat

Sample Output:

The longest palindrome substring of Habitat is: tat
----------------------------------------------------------------------------------------------------------------
i am able to write the code with out using pointers can any one help me regarding this how can i write this using pointers

code with out pointers is

#include<stdio.h>
#include<conio.h>
#include<string.h>
main()
{
char s[20],x[20],y[10],t[10];
int i,j,l,k,l1=0;
printf("Enter the string");
gets(s);
l=strlen(s);
s[l]='\0';
for(i=0;i<l;i++)
{
j=0;
x[j]=s[i]; //taking the first character into X
j++;
x[j]='\0';
for(k=i+1;k<l;k++)
{
x[j]=s[k];
j++;
x[j]='\0';
strcpy(t,x);
if(strcmp(t,strrev(x))==0) //comparing the substring as if palindrome
{
if(l1<strlen(x)) //if palindrome compare the length wih previous paindrome
{
strcpy(y,t);
puts(y); //print the longer palindrome
l1=strlen(y);
}
}

strrev(x);
}

}
getch();
}

Hi,

You can use array of char like char * x = new char[]; instead of char x[n]. I am not able to find anything else in this code where you can use pointers.

Regards

[ilikepython]

hi friends,
i am new to this can any one help me regarding this issue
my aim is to Write a program which computes the largest palindrome substring of a string using pointers

Input: The input is the string whose largest palindrome substring should be found.

Output: The output displays the largest palindrome substring.

Sample Input:

Enter the string: Habitat

Sample Output:

The longest palindrome substring of Habitat is: tat
----------------------------------------------------------------------------------------------------------------
i am able to write the code with out using pointers can any one help me regarding this how can i write this using pointers

code with out pointers is

#include<stdio.h>
#include<conio.h>
#include<string.h>
main()
{
char s[20],x[20],y[10],t[10];
int i,j,l,k,l1=0;
printf("Enter the string");
gets(s);
l=strlen(s);
s[l]='\0';
for(i=0;i<l;i++)
{
j=0;
x[j]=s[i]; //taking the first character into X
j++;
x[j]='\0';
for(k=i+1;k<l;k++)
{
x[j]=s[k];
j++;
x[j]='\0';
strcpy(t,x);
if(strcmp(t,strrev(x))==0) //comparing the substring as if palindrome
{
if(l1<strlen(x)) //if palindrome compare the length wih previous paindrome
{
strcpy(y,t);
puts(y); //print the longer palindrome
l1=strlen(y);
}
}

strrev(x);
}

}
getch();
}

Maybe you could use pointers to iterate over the string:

char test[] = "Hello World";
char *p;
for (p = test; *p != '\0'; p++;)
{
    // here use "*p" to get the char instead of "test[i]"
}
 

[weaknessforcats]

It looks like you are going to a lot of unnecessary work. A palindrome is a word or phrase that reads the saem in both directions.

So, you create two pointers A and B. Start A with the the address of element 0 and start B with the address of the element returned by strlen().

Compare the characters pointed at by the two pointers. If they are equal advance A by 1 and reduce B by 1 and repeat the compare.

You have a palindrome when the addresses in A and B are the same.