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# Python – Concatenate Strings in the Given Order

• Last Updated : 11 Oct, 2020

Given a String List and order list, perform string concatenation in specific order.

Input : test_list = [“best”, “Gfg”, “for”, “is”], sort_order = [1, 3, 0, 2]
Output : Gfgisbestfor
Explanation : Combined as per order of indices.
Input : test_list = [“best”, “Gfg”], sort_order = [1, 0]
Output : Gfgbest
Explanation : Combined as per order of indices.

Method #1 : Using loop

In this, we iterate order elements in loop, and perform concatenation of strings of similar index in similar order.

## Python3

 `# Python3 code to demonstrate working of ``# Concatenate Strings in Order``# Using loop`` ` `# initializing list``test_list ``=` `[``"best"``, ``"Gfg"``, ``"for"``, ``"is"``, ``"geeks"``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing join order ``sort_order ``=` `[``1``, ``3``, ``0``, ``2``, ``4``]`` ` `res ``=` `''``for` `ordr ``in` `sort_order:``     ` `    ``# concatenating by order ``    ``res ``+``=` `test_list[ordr]`` ` `# printing result ``print``(``"Ordered concatenation : "` `+` `str``(res))`
Output

```The original list is : ['best', 'Gfg', 'for', 'is', 'geeks']
Ordered concatenation : Gfgisbestforgeeks

```

Method #2 : Using join() + list comprehension

In this, we perform task of concatenation using join(), list comprehension is used for iteration of order.

## Python3

 `# Python3 code to demonstrate working of ``# Concatenate Strings in Order``# Using join() + list comprehension`` ` `# initializing list``test_list ``=` `[``"best"``, ``"Gfg"``, ``"for"``, ``"is"``, ``"geeks"``]`` ` `# printing original list``print``(``"The original list is : "` `+` `str``(test_list))`` ` `# initializing join order ``sort_order ``=` `[``1``, ``3``, ``0``, ``2``, ``4``]`` ` `# join() performs concatenation``res ``=` `''.join([test_list[ordr] ``for` `ordr ``in` `sort_order])`` ` `# printing result ``print``(``"Ordered concatenation : "` `+` `str``(res))`

Output
```The original list is : ['best', 'Gfg', 'for', 'is', 'geeks']
Ordered concatenation : Gfgisbestforgeeks

```

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