bzoj1087: [SCOI2005]互不侵犯King

状态压缩Dp，要与处理哪个可以转移到哪个

const int N = 10, K = 100, M = 1024;
struct Edge {
	int V;
	Edge *Next;
	Edge() {}
	Edge(int _V, Edge *_Next) : V(_V), Next(_Next) {}
} *Fir[M];
vector<int> State, Num;
int n, m;
LL Dp[N][K][M], Tot;

inline void Input() {
	scanf("%d%d", &n, &m);
}

inline void Search(int Now, int Scene) {
	if(!Now) {
		int T = Scene, num = 0;
		for(; T; T >>= 1) num += T & 1;
		if(num <= m) State.pub(Scene), Num.pub(num);
	} else {
		Search(Now - 1, Scene << 1);
		if(!(Scene & 1)) Search(Now - 1, (Scene << 1) | 1);
	}
}

inline bool Check(int x, int y) {
	return !((x & y) || ((x << 1) & y) || (x & (y << 1)));
}

inline void Solve() {
	Search(n, 0);
	Tot = sz(State);
	Rep(i, Tot) {
		rep(j, i + 1, Tot)
			if(Check(State[i], State[j]))
				Fir[i] = new Edge(j, Fir[i]), Fir[j] = new Edge(i, Fir[j]);
		if(!State[i]) Fir[i] = new Edge(i, Fir[i]);
	}
	
	Rep(i, Tot) Dp[1][Num[i]][i] = 1;
	rep(i, 1, n) {
		For(k, 0, m)
			Rep(j, Tot) {
				int v;
				LL T = Dp[i][k][j];
				if(!T) continue;
				for(Edge *Tab = Fir[j]; Tab != NULL; Tab = Tab->Next)
					if(k + Num[v = Tab->V] <= m) Dp[i + 1][k + Num[v]][v] += T;
			}
	}
	
	LL Ans = 0;
	Rep(i, Tot) Ans += Dp[n][m][i];
	cout << Ans << endl;
}

int main() {
	#ifndef ONLINE_JUDGE
	SETIO("1087");
	#endif
	Input();
	Solve();
	return 0;
}