performing topological sort

topologicalSort.cpp

int deg[maxn], rank[maxn];

void topologicalSort()
{
	queue<int> q;
	for(int i = 1; i <= n; i++)
	{
		if(deg[i] == 0)
		{
			rank[i] = 0;
			q.push(i);
		}
	}

	while(!q.empty())
	{
		int v = q.front());
		q.pop();

		for(int i = 0; i < e[v].size(); i++)
		{
			deg[e[v][i]]--;
			if(deg[e[v][i]] == 0)
			{
				rank[e[v][i]] = rank[v] + 1;
				q.push(e[v][i]);
			}
		}
	}
}