CareerCup

Nice que.

What about following logic:

reverse the bits of number for example number is 01100110
int dig = 1;
int rev = 0;
for(i=0;i<8;++i)
{
if(number & (dig<<i))
rev = pow(2,(7-i)) + rev;
}

if(! rev ^ number)
{
print palindrom
}
else
{
print bye-bye :)
}

didnt get the question
suppose how 0110 be a palindrome????
wy are u taking the leading zero if i take like this 0110= 0000110 then????
i think we should take till 1 means 6=110 is it or please elaborate what to do ??

Rahul is right. Although I would've preferred using scanf() to create two strings nd using strcmp()

bool isPalindrome(int num)
{
	int revNum=0;
	int temp=num;
	while(temp)
	{
		revNum = (revNum<<1)|(temp&1);
		temp=temp>>1;
	}
	temp=num;
	while((temp&1)==0)
	{
		revNum = revNum<<1;
		temp=temp>>1;
	}
	return ((num&revNum)==num)?true:false;
}

#include<iostream>
using namespace std;
#include<stdlib.h>
#include<string.h>

char *convert(int num)
{
char *str=new char(20);
char *st="0123456789";
int x,i=0;;
while(num)
{
x=num%2;
str[i++]=st[x];
num=num>>1;
}
str[i]='\0';
return str;
}

bool check(char *str)
{
int flag=1;
for(int i=0,j=strlen(str)-1;i<=j;i++,j--)
{
if(str[i]==str[j])
flag=1;
else
{
flag=0;
break;
}
}
if(flag)
return true;
else
return false;
}

int main()
{
int num;
cout<<"entr num\n";
cin>>num;
char *str=new char(20);
strcpy(str,convert(num));
if(check(str))
cout<<"is palin\n";
else
cout<<"not a palindrom\n";
return 0;
}

I'm considering all the bits of the given number. So let N is the original number. Now initially nLeft = N and nRight = N. nLeft & nRight represent result of the number N when its left & right shifted by 1 respectively. Algo is as follows:

while (nLeft != 0 && nRight != 0)
{
 if (first bit of nRight != last bit of nLeft)
 {
    number is not palindrom
    break;
 }
  nRight = nRight >> 1;
  nLeft = nLeft << 1;
}

if (nLeft == nRight)
{
  number is palindrom
}

Hope I'm clear enough. Plz comment on the approach.

// Since Character is unsigned short :) - Check with any 16 bit palindrome
	private boolean CheckBits(Character val,int n)
	{
		if(n > Character.SIZE-n-1)
			return true;
		if(((val >> n)&1) == ((val >> Character.SIZE-n-1)&1))
			{
			return CheckBits(val, n+1);
			}
		return false;
	}