CareerCup

1. Take two pointer start and end
2. keep swaping start and end , till start and end do not cross each other.

forget to mentione
one will need to forward start pointer and backward the end pointer.

#include "iostream"
#include "string.h"
using namespace std;

int main(){
char str1[]="Hello World!";
char *p = str1;
char *q = str1 + strlen(str1)-1;
char t;

cout << str1 << endl;

while(p < q){
t = *p;
*p = *q;
*q = t;
p++;
q--;
};

cout << str1 << endl;

}

#include <iostream>
#include <string>
using namespace std;

int main(){
char str[]="Hello World!";
int len = str.length();
for(int i=0;i<len/2;++i)
swap(&str[i],&str[len-i-1]);
}

void swap(char* a,char* b){
a = a^b;
b = a^b;
a = a^b;
}

mystr = ['c', 'o', 'd', 'i', 'n', 'g', ' ', 'i', 's', ' ', 'f', 'u', 'n']

for i in range(0, len(mystr)):
  j = (len(mystr)-i) - 1
  if i == j or i > j:
    break
  e = mystr[j]
  mystr[j] = mystr[i] 
  mystr[i] = e

print mystr

void reverseString(char *s)
{
int start = 0;
int len = strlen(s);
int end = len-1;
while(start<end)
{
s[start]= s[start]^s[end];
s[end] = s[start]^s[end];
s[start]= s[start]^s[end];
start++;end--;
}
s[len]='\0';
}

reverse(char *c,int l)
{
char *p,*q;
p=c;
q=c+l-1;
while(*p!=*q)
{
ch=*p;
*p=*q;
*q=ch;
p++;
q--;
}

return;
}

int i=0,rev_len = strlen(reverse);
for(i=0;i < (rev_len/2);i++) {
temp = reverse[rev_len-i-1];
reverse[rev_len-i-1] = reverse[i];
reverse[i] = temp;
}

#define REVERSE_STRING(X) Rstring(X, *(X), strlen(X)-1)

void Rstring( char *str, char c, int index )
{
if( index != 0 )
Rstring( str, *(str+(strlen(str))-index),index-1);
*(str+index) = c;
}