SRM 597 DIV2 250

Problem Statement
	Little Elephant from the Zoo of Lviv likes integers. You are given an vector <int> A. On a single turn, Little Elephant can double (i.e., multiply by 2) any element of A. He may double the same element more than once, if he wants to. He wants to obtain an array in which all elements are equal. Return "YES" (quotes for clarity) if it is possible to do that and "NO" otherwise.
Definition
	Class: LittleElephantAndDouble Method: getAnswer Parameters: vector <int> Returns: string Method signature: string getAnswer(vector <int> A) (be sure your method is public)
Notes
-	The return value is case-sensitive. Make sure that you return the exact strings "YES" and "NO".
Constraints
-	A will contain between 1 and 50 elements, inclusive.
-	Each element of A will be between 1 and 1,000,000,000, inclusive.
Examples
0)
	{1, 2} Returns: "YES" One possible way of making all elements equal is to double the element at index 0.
1)
	{1, 2, 3} Returns: "NO" It's impossible to make all three elements equal in this case.
2)
	{4, 8, 2, 1, 16} Returns: "YES"
3)
	{94, 752, 94, 376, 1504} Returns: "YES"
4)
	{148, 298, 1184} Returns: "NO"
5)
	{7, 7, 7, 7} Returns: "YES"

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#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <ctime>

using namespace std;

class LittleElephantAndDouble {
public:
string getAnswer(vector <int>);
};

bool ck(int x)
{
int lb=x&(-x);
return x==lb;
}

string LittleElephantAndDouble::getAnswer(vector <int> A) {
int Max=-999999,t=A.size();
bool flag=true;
string Yes("YES"),No("NO");
for(int i=0;i<t;i++) Max=max(Max,A[i]);
for(int i=0;i<t;i++)
{
if(A[i]==Max) continue;
if(Max%A[i]!=0) {flag=false;break;}
if(ck(Max/A[i])==false) {flag=false;break;}
}
if(flag) return Yes;
else return No;
}

//<%:testing-code%>
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