Python | Replace elements in second list with index of same element in first list

Given two lists of strings, where first list contains all elements of second list, the task is to replace every element in second list with index of elements in first list.

Method #1: Using Iteration

# Python code to replace every element  
# in second list with index of first element. 
  
# List Initialization 
Input1 = ['cut', 'god', 'pass']  
Input2 = ['god', 'cut', 'cut', 'cut',  
          'god', 'pass', 'cut', 'pass'] 
  
# List Initialization 
Output = [] 
  
# Using iteration 
for x in Input2: 
    for y in Input1: 
        if x == y: 
            Output.append(Input1.index(y)) 
  
# Printing output 
print("initial 2 list are") 
print(Input1, "\n", Input2) 
print("Second list after replacement is:", Output) 

Output:

initial 2 list are
['cut', 'god', 'pass'] 
 ['god', 'cut', 'cut', 'cut', 'god', 'pass', 'cut', 'pass']
Second list after replacement is: [1, 0, 0, 0, 1, 2, 0, 2]

Method #2: Using List comprehension

# Python code to replace every element  
# in second list with index of first element. 
  
# List initialization 
Input1 = ['cut', 'god', 'pass'] 
  
# using enumeate 
temp = {y:x for x, y in enumerate(Input1)} 
  
# List initialization 
Input2 = ['god', 'cut', 'cut', 'cut',  
          'god', 'pass', 'cut', 'pass'] 
  
# Using list comprehension 
Output = [temp.get(elem) for elem in Input2] 
  
# Printing output 
print("initial 2 list are") 
print(Input1, "\n", Input2) 
print("Second list after replacement is:", Output) 

Output:

initial 2 list are
['cut', 'god', 'pass'] 
 ['god', 'cut', 'cut', 'cut', 'god', 'pass', 'cut', 'pass']
Second list after replacement is: [1, 0, 0, 0, 1, 2, 0, 2]

Method #3 : Using map

# Python code to replace every element  
# in second list with index of first element. 
  
# List initialization 
Input1 = ['cut', 'god', 'pass'] 
  
# List initialization 
Input2 = ['god', 'cut', 'cut', 'cut', 
          'god', 'pass', 'cut', 'pass'] 
  
elem = {k: i for i, k in enumerate(Input1)} 
Output = list(map(elem.get, Input2)) 
  
# Printing output 
print("initial 2 list are") 
print(Input1, "\n", Input2) 
print("Second list after replacement is:", Output) 

Output:

initial 2 list are
['cut', 'god', 'pass'] 
 ['god', 'cut', 'cut', 'cut', 'god', 'pass', 'cut', 'pass']
Second list after replacement is: [1, 0, 0, 0, 1, 2, 0, 2]

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