BZOJ 3717: [PA2014]Pakowanie

对于包排序

状压DP

#include<cstdio>
#include<algorithm>
using namespace std;
int F[20000005],ID[20000005],G[20000005],a[105],v[105];
int lowbit(int x){
	return x&(-x);
}
bool cmp(long long a,long long b){
	return a>b;
}
int main(){
	int n,m;
	scanf("%d%d",&n,&m);
	for (int i=0; i<n; i++) scanf("%d",&a[i]);
	for (int i=0; i<m; i++) scanf("%d",&v[i]);
	sort(v,v+m,cmp);
	for (int i=0; i<(1<<n); i++) F[i]=1e9;
	for (int i=0; i<n; i++) ID[1<<i]=i;
	F[0]=G[0]=-1;
	for (int now=1; now<(1<<n); now++){
		for (int j=now; j; j-=lowbit(j)){
			int i=lowbit(j);
			int f=F[now-i],g=G[now-i];
			if (f>n) continue;
			int tof=f,tog=g-a[ID[i]];
			if (tog<0) tof++,tog=v[tof]-a[ID[i]];
			if (tog>=0 && (tof<F[now] || tof==F[now] && tog>G[now])) F[now]=tof,G[now]=tog;
		}
	}
	if (F[(1<<n)-1]!=1e9) printf("%d\n",F[(1<<n)-1]+1);
	else printf("NIE\n");
	return 0;
}