bzoj1925

dp

搬题解~~:http://blog.csdn.net/aarongzk/article/details/44871391

#include<cstdio>
using namespace std;
const int N = ;
int n, p, pre;
int f[][N];
int main()
{
    scanf("%d%d", &n, &p);
    f[pre][] = ;
    for(int i = ; i <= n; ++i)
    {
        pre ^= ;
        for(int j = ; j <= n; ++j) f[pre][j] = (f[pre][j - ] + f[pre ^ ][i - j]) % p;
    }
    if(n == ) puts("");
    else printf("%d\n", (f[pre][n] << ) % p);
    return ;
}