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 1
4 2

Sample Output

1
0

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;  
}