[BZOJ] 1334: [Baltic2008]Elect

先按物品总价降序排序，背包容量限制在(dfrac m2+a[i])即可

排序可以用greater<int>()，省写cmp

#include<algorithm>
#include<iostream>
#include<cstdio>

using namespace std;

inline int rd(){
	int ret=0,f=1;char c;
	while(c=getchar(),!isdigit(c))f=c=='-'?-1:1;
	while(isdigit(c))ret=ret*10+c-'0',c=getchar();
	return ret*f;
}

const int MAXN = 10005;

int n,m,ans;
int a[MAXN],f[100005];

int main(){
	n=rd();
	for(int i=1;i<=n;i++)m+=(a[i]=rd());
	sort(a+1,a+1+n,greater<int>());
	f[0]=1;
	for(int i=1;i<=n;i++){
		for(int j=m/2+a[i];j>=a[i];j--){
			if(f[j-a[i]]){
				f[j]=1;
				ans=max(ans,j);
			}
		}
	}
	cout<<ans<<endl;
	return 0;
}