UVALive 7278 Game of Cards

题目链接：https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&page=show_problem&problem=5330



题意：有n堆卡片，每张卡片上面都有一个数字（1~10），每次操作选择一堆卡片，取走最上面（0~k）张，一堆至少要留一张，然后再取这堆卡片当前堆顶卡片上面的数字张数。谁不能取就输了。



思路：组合游戏博弈，直接暴力计算出每一堆的sg函数即可。



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

#define rep(i,j,k) for (int i=j;i<=k;i++)
#define Rrep(i,j,k) for (int i=j;i>=k;i--)

#define Clean(x,y) memset(x,y,sizeof(x))
#define LL long long
#define ULL unsigned long long
#define inf 0x7fffffff
#define mod 100000007
const int maxn = 1009;

int p,k;
int a[maxn];

int cal(int n)
{
int sg[maxn];
int temp[50];
Clean(sg,0);
rep(i,1,n)
{
Clean(temp,false);
rep(j,0,k)
if ( i > j && i - j >= a[i-j] )
temp[ sg[i-j-a[i-j]] ] = true;
int j = 0;
while(temp[j]) j++;
sg[i] = j;
}
return sg
;
}

void solve()
{
int m;
int ans = 0;
rep(i,1,p)
{
scanf("%d",&m);
rep(j,1,m) scanf("%d",&a[j]);
ans ^= cal(m);
}
puts(ans?"Alice can win.":"Bob will win.");
}

int main()
{
while( cin>>p>>k )
{
solve();
}
return 0;
}