Cycle Finding

You are given a directed graph, and your task is to find out if it contains a negative cycle, and also give an example of such a cycle. Input The first input line has two integers n and m: the number of nodes and edges. The nodes are numbered 1,2,\ldots,n. After this, the input has m lines describing the edges. Each line has three integers a, b, and c: there is an edge from node a to node b who