The Tech Street

#!/usr/bin/env python import collections graph = {'A': ['B', 'C'],              'B': ['C', 'D'],              'C': ['D'],              'D': ['C'],              'E': ['F'],              'F': ['C']} #Using DFS algorithm #Ref -   https://www.python.org/doc/essays/graphs/ def find_all_paths_dfs(graph, start, end, path = []):   path = path + [start]   #Reachd end return path   if start == end:         return [path]   #No path found found   if not graph.has_key(start):         return []   paths = []   for node in graph[start]:     if node not in path:       new_paths = find_all_paths_dfs(graph, node, end, path)       for new...

Ascii to Integer Input - '123' Output - 123 def atoi (s):   res = 0   for i in range ( len (s)):     n = ord (s[i]) - ord ( '0' )     res = res * 10 + n   return res