Luogu P4394 [BOI2008]Elect 选举

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;

int n,a[100005],dp[100005],sum,half,ans;

int main(){
    scanf("%d",&n);
    for(int i=1;i<=n;i++){
        scanf("%d",&a[i]);
        sum+=a[i];
    }
    half=sum>>1;
    sort(a+1,a+n+1);
    for(int i=n;i>=1;i--){
        for(int j=sum;j>=0;j--){
            if(j>=a[i])dp[j]=max(dp[j],dp[j-a[i]]+a[i]);
            if(dp[j]>half&&dp[j]-a[i]<=half){
                ans=max(ans,dp[j]);
            }
        }
    }
    printf("%d\n",ans);
}