HDU 1233 还是畅通工程

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;
const int MAX = 105;
int fa[MAX], r[MAX];
struct EDGE
{
int from, to, cost;
}edge[MAX * MAX];

bool comp(EDGE a, EDGE b)
{
return a.cost < b.cost;
}

void init(int n)
{
for (int i = 1; i <= n; ++i)
{
fa[i] = i;
r[i] = 1;
}
}

int find(int x)
{
return fa[x] == x ? x : fa[x] = find(fa[x]);
}

void unite(int a, int b)
{
a = find(a);
b = find(b);
if (a == b)
return ;
if (r[a] < r[b])
{
fa[a] = b;
}
else
{
fa[b] = a;
if (r[a] == r[b])
r[a]++;
}
}

int main()
{
int n;
while (scanf("%d", &n))
{
if (n == 0)
break;
int t_from, t_to, t_cost;
init(n);
int cnt = 0;
//cout << n << endl;
n = n * (n - 1) / 2;
//printf("n = %d\n", n);
for (int i = 1; i <= n; ++i)
{
scanf("%d%d%d", &t_from, &t_to, &t_cost);
++cnt;
edge[cnt].from = t_from;
edge[cnt].to = t_to;
edge[cnt].cost = t_cost;
}
int res = 0;
sort(edge + 1, edge + 1 + cnt, comp);
for (int i = 1; i <= cnt; ++i)
{
if(find(edge[i].from) != find(edge[i].to))
{
res += edge[i].cost;
unite(edge[i].from, edge[i].to);
}
}
printf("%d\n", res);
}

return 0;
}