How to solve TypeError: can only concatenate list (not “int”) to list

In this article, you will learn how to solve TypeError: can only concatenate list (not “int”) to list Python error.

Let’s look at a code example that produces the same error.

fruits = ["mango and orange", "pineapple", "grapes and black grapes", "banana"]
buy_price = [100, 200, 300, 400]
fruits_bought = []
for s in range(0, len(fruits)):
 if buy_price[s] > 100:
  fruits_bought = fruits_bought + s
for o in fruits_bought:
 print(fruits[o])

Output

Traceback (most recent call last):
  File "<string>", line 6, in <module>
TypeError: can only concatenate list (not "int") to list

In order to solve TypeError: can only concatenate list (not “int”) to list Python error you have to use the append() method to add an item to your list. consider the example below:

fruits = ["mango and orange", "pineapple", "grapes and black grapes", "banana"]
buy_price = [100, 200, 300, 400]
fruits_bought = []
for s in range(0, len(fruits)):
 if buy_price[s] > 100:
  fruits_bought.append(s)
for o in fruits_bought:
 print(fruits[o])

output

pineapple
grapes and black grapes
banana