IO Stream performance.

Many of  the competitive programming portals available on the web advice –for certain problems involving huge input reading or output printing– the user to avoid cin/cout in spite of printf/scanf: As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use scanf/printf instead of cin/cout in C++, prefer to use […]

Magic paths!

Hi! There are  lot of problems related with finding the shortes or the longest path in graph, most of them using forms of DFS,BFS or in case of weighted graph using the Dijkstra algorithm, Bellman-Ford or one of the many other. Let’s see one of those problem: Given a weighted –no negative weights– connected graph […]