Coursera Algorithm Part II PA2

class Edge{
public:
	int start;
	int end;
	int cost;
public:
	Edge(int st, int ed, int cst):start(st),end(ed),cost(cst) {}
	Edge(){
		Edge(0, 0, 0);
	}
	bool operator<(const Edge &other) {
		return (cost < other.cost)? true:false;
	}
	bool operator<(const Edge &other) const {
		return (cost < other.cost)? true:false;
	}
};
int  curSize = 0;
vector minHeap;
const int maxVertex = 500;
int numCluster = maxVertex;
int cluster[maxVertex+1];
const int K = 4;
 
void init() {
	for(int i = 1; i <= maxVertex; i ++) {
		cluster[i] = i;
	}
}
int findSet(int vertex) {
	if(cluster[vertex] != vertex) {
		cluster[vertex] = findSet(cluster[vertex]);
	}
	return cluster[vertex];
}
bool mergeSet(int start, int end) {
	int faStart = findSet(start);
	int faEnd = findSet(end);
	if(faStart != faEnd) {
		cluster[faEnd] = faStart;
		return true;
	}
	return false;
}
 
int main() {
	int start, end, cost;
	int curVertex = maxVertex;
	Edge edge;
	scanf("%d", &start);
	init();
	minHeap.reserve(130000);
	while(scanf("%d%d%d", &start, &end, &cost)!=EOF) {
		minHeap.push_back(Edge(start, end, cost));
		curSize++;
	}
	sort(minHeap.begin(), minHeap.end());
	vector::iterator vec_it;
	for(vec_it = minHeap.begin(); curVertex > K; vec_it++) {
		if(mergeSet(vec_it->start, vec_it->end))
			curVertex--;
	}
	vec_it--;
	// 找到 cluster 之间的最小距离
	for(; ;vec_it++) {
		if(findSet(vec_it->start) != findSet(vec_it->end) ) {
			cout << (vec_it)->cost <<endl;
			cout << "sss"<<endl;
			break;
		}
	}
	return 0;
}