[ENHANCEMENT] Include Time and Space Complexity Information #698

Added time and space complexity for Bellman-Ford, find cycle and depth first search implementations

Author: donutt03

graph/bellmanford.go

@@ -3,6 +3,8 @@
 // It is slower than Dijkstra but capable of handling negative edge weights.
 // https://en.wikipedia.org/wiki/Bellman%E2%80%93Ford_algorithm
 // Implementation is based on the book 'Introduction to Algorithms' (CLRS)
+// Worst Case Time Complexity: O(V * E)
+// Auxiliary Space: O(V)
 
 package graph
 

graph/cycle.go

@@ -5,6 +5,8 @@
 
 package graph
 
+// Worst Case Time Complexity: O(V + E)
+// Auxiliary Space: O(V)
 func (g *Graph) HasCycle() bool {
 	//this implimetation referred as 3-color too
 	all := map[int]struct{}{}
@@ -45,6 +47,8 @@ func (g Graph) hasCycleHelper(v int, all, visiting, visited map[int]struct{}) bo
 }
 
 // this function can do HasCycle() job but it is slower
+// Worst Case Time Complexity: O(V + E)
+// Auxiliary Space: O(V)
 func (g *Graph) FindAllCycles() []Graph {
 	all := map[int]struct{}{}
 	visiting := map[int]struct{}{}

graph/depthfirstsearch.go

@@ -1,3 +1,6 @@
+// Worst Case Time Complexity: O(V + E)
+// Auxiliary Space: O(V)
+
 package graph
 
 func GetIdx(target int, nodes []int) int {