数论(Lucas定理) HDOJ 4349 Xiao Ming's Hope

/************************************************
* Author        :Running_Time
* Created Time  :2015-8-27 8:48:05
* File Name     :J.cpp
************************************************/

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <sstream>
#include <cstring>
#include <cmath>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <list>
#include <map>
#include <set>
#include <bitset>
#include <cstdlib>
#include <ctime>
using namespace std;

#define lson l, mid, rt << 1
#define rson mid + 1, r, rt << 1 | 1
typedef long long ll;
const int N = 1e5 + 10;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;

int main(void)    {
int n;
while (scanf ("%d", &n) == 1)	{
int cnt = 0;
while (n)	{
if (n & 1)	cnt++;
n >>= 1;
}
ll ans = 1;
for (int i=1; i<=cnt; ++i)	ans *= 2;
printf ("%I64d\n", ans);
}

return 0;
}