The Gray-Similar Code
All submissions for this problem are available.
The Gray code (see wikipedia for more details) is a well-known concept.
One of its important properties is that every two adjacent numbers have exactly one different digit in their binary representation.
In this problem, we will give you n non-negative integers in a sequence A[1..n] (0<=A[i]<2^64), such that every two adjacent integers have exactly one different digit in their binary representation, similar to the Gray code.
Your task is to check whether there exist 4 numbers A[i1], A[i2], A[i3], A[i4] (1 <= i1 < i2 < i3 < i4 <= n) out of the given n numbers such that A[i1] xor A[i2] xor A[i3] xor A[i4] = 0. Here xor is a bitwise operation which is same as ^ in C, C++, Java and xor in Pascal.
First line contains one integer n (4<=n<=100000).
Second line contains n space seperated non-negative integers denoting the sequence A.
Output “Yes” (quotes exclusive) if there exist four distinct indices i1, i2, i3, i4 such that A[i1] xor A[i2] xor A[i3] xor A[i4] = 0. Otherwise, output "No" (quotes exclusive) please.
Input: 5 1 0 2 3 7 Output: Yes
|Tags||july12, medium, pigeonhole, search, shangjingbo|
|Time Limit:||0.1 - 0.107125 sec|
|Source Limit:||50000 Bytes|
|Languages:||C, CPP14, JAVA, PYTH, PYTH 3.5, CS2, PAS fpc, PAS gpc, RUBY, PHP, GO, NODEJS, HASK, SCALA, D, PERL, FORT, WSPC, ADA, CAML, ICK, BF, ASM, CLPS, PRLG, ICON, SCM qobi, PIKE, ST, NICE, LUA, BASH, NEM, LISP sbcl, LISP clisp, SCM guile, JS, ERL, TCL, PERL6, TEXT, CLOJ, FS|
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