[욕심DP] BZOJ 4069 [Apio 2015] 발리의 조각

#include<cstdio>
#include<cstdlib>
#include<algorithm>
using namespace std;
typedef long long ll;

inline char nc()
{
	static char buf[100000],*p1=buf,*p2=buf;
	if (p1==p2) { p2=(p1=buf)+fread(buf,1,100000,stdin); if (p1==p2) return EOF; }
	return *p1++;
}

inline void read(int &x)
{
	char c=nc(),b=1;
	for (;!(c>='0' && c<='9');c=nc()) if (c=='-') b=-1;
	for (x=0;c>='0' && c<='9';x=x*10+c-'0',c=nc()); x*=b;
}

int n,A,B,len;
ll sum[2005],ans;
int f[105][105],g[2005];

int main()
{
	int ia; ll itmp;
	freopen("t.in","r",stdin);
	freopen("t.out","w",stdout);
	read(n); read(A); read(B);
	for (int i=1;i<=n;i++) read(ia),sum[i]=sum[i-1]+ia;
	for (;(1LL<<len)<sum[n];len++);
	if (A==1)
	{
		for (;~len;len--)
		{
			for (int i=1;i<=n;i++)
			{
				g[i]=n+1;
				for (int j=0;j<i;j++)
				{
					itmp=sum[i]-sum[j];
					if (((itmp>>(len+1))|ans)==ans && ((itmp>>len)&1)==0)
						g[i]=min(g[i],g[j]+1);
				}
			}
			ans=(ans<<1)|(g[n]>B);
		}
	}
	else
	{
		f[0][0]=1;
		for (;~len;len--)
		{
			for (int i=1;i<=n;i++)
				for (int j=1;j<=i && j<=B;j++)
				{
					f[i][j]=0;
					for (int k=0;k<i && f[i][j]==0;k++)
					{
						if (!f[k][j-1]) continue;
						itmp=sum[i]-sum[k];
						if (((itmp>>(len+1))|ans)==ans && ((itmp>>len)&1)==0)
							f[i][j]=1;
					}
				}
			int flag=1;
			for (int i=A;i<=B && flag;i++) if (f[n][i]) flag=0;
			ans=(ans<<1)|flag; 
		}
	}
	printf("%lld
",ans);
	return 0;
}