@vijju123 Finally, implemented the code… And, everything came out correctly…
Thank you once again for your assistance… Without you, I guess, I would’ve still have been stuck in a mire…
CS is truly an amazing community… And, I am glad that I am a part of it…
Our community reminds me of a quote said by Professor Albus Dumbledore:
“At Hogwarts, help is always given to those who seek it.” Just replace ‘At Hogwarts’ with ‘In CS’
What a question,i thought i was so close to the solution but then i thought to give a read to the editorial because i was not so sure and when i saw the question i waas far away from the real solution.Great Question ! Learnt new things from this question.
The main focus point towards solving this problem is
"XOR" operation is commutative.
A very nice trick by the problem setter, at first it seemed too much, enjoyed it.
p1,p2,p3 are order in which you traverse the points.
I am glad it helped dear 
Is there a way to rate a problem??
In that case, I would like to rate it 5 stars
someone help me please im still new in this C programing
#include <stdio.h>
int main()
{
int a = 0, b = 0 ,c = 1;
int n = 0;
scanf("%d",&n);
for(int i = 1; i <= n; i++){
scanf("%d",&a);
}
for(int j = 1; j <= a;j++){
scanf("%d %d",&b,&c);
b ^= c;
printf("%d",b);
}
return 0;
}
I didn’t saw problem title when I started solving this problem, and I thought what kind of joke is this?
Then after submitting when I was saving problem link in my solved problems list and saw the problem code and then title. Literally, what a Good Joke! 
really u explain its very well.I am also confused about this Q,and now my every confusion is clear.thanks alot .
such a difficult problem, Tester’s solution is not yet even available yet. 
same here i am watching my first editorial and it is very shameful for me also but at least i did not waste my 2 to 3 days finding original solution
kinda feeling same like you bro 