zoj 2996 (1+x)^n

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(1+x)^n

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Time Limit: 2 Seconds      Memory Limit: 65536 KB

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Please calculate the coefficient modulo 2 of x^i in (1+x)^n.

Input

For each case, there are two integers n, i (0<=i<=n<=2^31-1)

Output

For each case, print the coefficient modulo 2 of x^i in (1+x)^n on a single line.

Sample Input

3 14 2

Sample Output

10

我自己想不出来，只能是没听过这个知识点，判断C(n,i)的奇偶性，如果它是奇数就满足（n&i）==i

#include<iostream>  using namespace std;  int main()  {      int n,i;      while(cin>>n>>i)      {          if((n&i)==i)              cout<<1<<endl;          else              cout<<0<<endl;      }      return 0;  }