1. A method for ranking nodes in a graph, wherein the method comprises: computing resultant path strength between each pair of nodes in a polynomial time; determining a first node based on resultant path strength such that total path strength to the first node is a maximum value; iteratively determining a next node from the first node to which the resultant path strength is a maximum value and the node is not visited; and providing each determined node a unique rank value, and ranking the nodes in an order determined by the unique rank value of each node.