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#include <iostream> #include <cstdio> #include <algorithm> #include <cstring> #include <cmath> #include <queue> #include <vector> #define MID(x,y) ((x+y)>>1) #define iabs(x) ((x)>0?(x):-(x)) using namespace std; #define maxn 100 int st[maxn]; int n,side; bool vis[maxn]; bool cmp(int a,int b) { return a>b; } bool dfs(int bian,int len,int id) { if(bian==3) return 1; vis[id]=1; for(int i=id;i<n;i++) if(!vis[i]){ if(len+st[i]>side) continue; vis[i]=1; if(len+st[i]==side&&dfs(bian+1,0,0)) return 1; if(len+st[i]<side&&dfs(bian,len+st[i],i)) return 1; vis[i]=0; } return 0; }
int main(){ int t; scanf("%d",&t); while(t--) { memset(vis,0,sizeof(vis)); scanf("%d",&n); int total=0; for(int i=0;i<n;i++) { scanf("%d",&st[i]); total+=st[i]; } if(total%4!=0){ printf("non"); continue; } side=total/4; sort(st,st+n,cmp); if(st[0]>side){ printf("non"); continue; } if(dfs(0,0,0)){ printf("yesn"); } else printf("non"); } return 0; }
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