﻿ Python: Decode a run-length encoded given list - w3resource

# Python: Decode a run-length encoded given list

## Python List: Exercise - 77 with Solution

Run-length encoding (RLE) is a form of lossless data compression in which runs of data (sequences in which the same data value occurs in many consecutive data elements) are stored as a single data value and count, rather than as the original run.

Write a Python program to decode a run-length message.

Sample Solution:

Python Code:

``````def decode(alist):
def aux(g):
if isinstance(g, list):
return [(g, range(g))]
else:
return [(g, )]
return [x for g in alist for x, R in aux(g) for i in R]
n_list = [[2, 1], 2, 3, [2, 4], 5, 1]
print("Original encoded list:")
print(n_list)
print("\nDecode a run-length encoded said list:")
print(decode(n_list))
```
```

Sample Output:

```Original encoded list:
[[2, 1], 2, 3, [2, 4], 5, 1]

Decode a run-length encoded said list:
[1, 1, 2, 3, 4, 4, 5, 1]
```

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## Python: Tips of the Day

Given a predicate function, fn, and a prop string, this curried function will then take an object to inspect by calling the property and passing it to the predicate:

Example:

```def tips_check_prop(fn, prop):
return lambda obj: fn(obj[prop])
check_age = tips_check_prop(lambda x: x >= 25, 'age')
user = {'name': 'Owen', 'age': 25}

print(check_age(user))
```

Output:

```True
```

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