$RT$,$TLE$我能理解,但为什么会$WA$啊$QAQ$.

$Code:$

#include<bits/stdc++.h>
using namespace std;
#define N 121
#define re register
int cnt,n,a[N],b[N],sum,mina,nxt[N];
char vac[N];
bool cmp(int a,int b){return a>b;}
void DFS(int s,int old)
{
	re int kick=0;
	re int l=1,r=cnt,lef=0;
	while(l<=r)
	{
		re int mid=l+r>>1;
		if(a[mid]+old>s) l=mid+1;
		else r=mid-1,lef=mid;
	}
	if(!lef)return;
	for(re int i=lef;i<=cnt;++i)
	{
		if(vac[i]) continue;kick=1;
		if(old+a[i]!=s) vac[i]=1,DFS(s,old+a[i]),vac[i]=0;
		else vac[i]=1,DFS(s,0),vac[i]=0;
		i=nxt[i];
	}
	if(!kick&&!old) return printf("%d",s),exit(0);
	return;
}
int main()
{
	cin>>n;
	for(re int i=1;i<=n;++i) scanf("%d",b+i);
    for(re int i=1;i<=n;++i)
    {
        if(b[i]<=50)
        {
        	a[++cnt]=b[i],sum+=b[i],mina=max(mina,b[i]);
        	nxt[cnt]=cnt;
        }
    }
    sort(a+1,a+cnt+1,cmp);
    for(int i=1;i<=cnt;++i)
    {
    	for(int j=i+1;j<=cnt;++j)
    	if(a[i]!=a[j]) {nxt[i]=j-1;break;}
    }
	for(re int i=mina;i<=sum/2;++i)
	if(sum%i==0){DFS(i,0);}
	cout<<sum;
	return 0;
}