Python - List Concatenation and Repetition

  1. HOME
  2. Python
  3. List
  4. List Concatenation and Repetition

Introduction

Lists are sequences, therefore lists support many of the same operations as strings.

For example, lists respond to the + and * operators much like strings.

They mean concatenation and repetition here too:

Demo

print( len([1, 2, 3]) )                          # Length 
print( [1, 2, 3] + [4, 5, 6] )                   # Concatenation 
print( ['Ni!'] * 4 )                             # Repetition
# from ww  w.jav  a2s .  c o m

Result

You cannot concatenate a list and a string.

You have to first convert the list to a string using str or % formatting or convert the string to a list via the list built-in function:

Demo

print( str([1, 2]) + "34" )                       # Same as "[1, 2]" + "34" 
print( [1, 2] + list("34") )                      # Same as [1, 2] + ["3", "4"]

Result