Python really simple backtracking solution
\t\tdef maxLength(self, arr):\n\t\t\tself.maximum = 0\n\n\t\t\tdef backtrack(start,array,s):\n\t\t\t\tif len(s)==len(set(s)):\n\t\t\t\t\tself.maximum = max(self
\t\tdef maxLength(self, arr):\n\t\t\tself.maximum = 0\n\n\t\t\tdef backtrack(start,array,s):\n\t\t\t\tif len(s)==len(set(s)):\n\t\t\t\t\tself.maximum = max(self.maximum,len(s))\n\t\t\t\telse:\n\t\t\t\t\treturn\n\t\t\t\tfor i in range(start,len(array)):\n\t\t\t\t\tbacktrack(i+1,array,s + array[i])\n\n\t\t\tbacktrack(0,arr,"")\n\t\t\treturn self.maximum\n\t\t\t\n
['Backtracking', 'Python']