I have a dictionary, the keys are integer values and the values are a list of strings. I want to make it vice versa, the string become key and integers become values. Like:
first design:
{1:["a"], 2:["a","b"], 3:["a"], 4:["b", "cd"], 6:["a","cd"]}
second design:
{"a": [1,2,3,6], "b":[2,4], "cd":[4,6]}
any clue? Thanks