5.给定两个单向链表，计算两个链表的第一个公共节点，若没有公共节点，返回空。

int CalcLength(SNode *p){
	int nLen = 0;
	while (p){
		p = p->pNext;
		nLen++;
	}
	return nLen;
}

SNode *FindFirstSameNode(SNode *pA, SNode *pB){
	pA = pA->pNext;
	pB = pB->pNext;

	int nA = CalcLength(pA);
	int nB = CalcLength(pB);
	if (nA > nB){
		swap(pA, pB);
		swap(nA, nB);
	}

	for (int i = 0; i < nB - nA; i++)
		pB = pB->pNext;

	while (pA){
		if (pA == pB)
			return pA;
		pA = pA->pNext;
		pB = pB->pNext;
	}
	return NULL;
}

6.拓扑排序，结点数为n，用邻接矩阵graph[n][n]存储边权，用indegree[n]存储每个结点的入度

void topologic(int *toposort){
	int cnt = 0;
	queue<int> q;
	int i;
	for (i = 0; i < n; i++){
		if(indegree[i] == 0)
			q.push(i);
	}
	int cur;
	while(!q.empty()){
		cur = q.front();
		q.pop();
		toposort[cnt++] = cur;
		for(i = 0; i < n; i++){
			if (graph[cur][i] != 0){
				indegree[i]--;
				if(indegree[i] == 0)
					q.push(i);
			}
		}
	}
}