HDU 4277 USACO ORZ

#include<algorithm>
#include<iostream>
#include<cstring>
#include<vector>
#include<cstdio>
#include<cmath>
#include<set>

#define SL strlen
#define PB push_back
#define LL long long
#define INF 0X3f3f3f3f
#define CLR(a, b) memset(a, b, sizeof(a))

using namespace std;

const int N = 17;

struct triangular
{
int a, b, c;
bool operator < (const triangular& rhs) const
{
if(a != rhs.a) return a < rhs.a;
if(b != rhs.b) return b < rhs.b;
return c < rhs.c;
}
} tri;

set<triangular> hav;

int a[N], dp[1 << N];

bool ok(int a, int b, int c)
{
if(a + b > c && abs(a - b) < c) return 1;
return 0;
}

int check(int k)
{
int i = 0, ret = 0;
while(k)
{
if(k & 1) ret += a[i];
k >>= 1;i ++;
}
return ret;
}

int main()
{
//freopen("input.txt", "r", stdin);
int n, t, i, j, k, s, ans;
scanf("%d", &t);
while(t --)
{
scanf("%d", &n);
for(i = 0; i < n; i ++)
{
scanf("%d", &a[i]);
}
for(i = 1; i < (1 << n); i ++)
{
dp[i] = check(i);
}
ans = 0;
hav.clear();
for(i = 1; i < (1 << n); i ++)
{
k = (1 << n) - i - 1;
for(j = (k - 1) & k; j; j = k & (j - 1))
{
if(dp[j] >= dp[i])
{
s = (1 << n) - 1 - i - j;
if(dp[s] >= dp[j] && ok(dp[i], dp[j], dp[s]))
{
tri.a = dp[i], tri.b = dp[j], tri.c = dp[s];
if(!hav.count(tri))
{
ans ++;
hav.insert(tri);
}
}
}
}
}
printf("%d\n", ans);
}
}