穷举法和搜索法的统计三角形

#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
int n,l[15];
bool h[10000];
bool is_triangle(int a,int b,int c)
    {
    return !h[a * 100 + b] && a && b && c && a+b>c && a+c>b  && b+c>a && (h[a*100+b] = true);
}

int dfs(int index, int a,int b ,int c)
    {
    if (index ==n){
      return a<b && b<c && is_triangle(a,b,c);
    }

    return dfs(index +1, a+l[index],b,c) +dfs(index +1 ,a,b+l[index],c)+dfs(index+1,a,b,c+l[index]);
}
int main(){
    int T;
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        for(int i = 0; i< n; ++i)
        {
            scanf("%d",&l[i]);
        }
        memset(h,0,sizeof(h));
        printf("%d\n",dfs(0,0,0,0));
    }
    return 0;
}