## sorting
* **inversions** in a sequence is a pair of elements that are out of order with respect to the ordering relation. a sorting algorithm is a sequence of operations that reduces inversions to zero. * a **topological sort** of a diretect graph is a way of ordering the list of nodes such that if `(a, b)` is a edge of the graph, then `a` appears before `b`. it does not work if a graph has cycles or is not directed.
---- ### examples in this dir
#### `sorting_algorithms.py`
```python > python3 sorting_algorithms.py Array: [3, 5, 1, 2, 10, 6] Testing merge sort: [1, 2, 3, 5, 6, 10] Testing quick sort: [1, 2, 3, 5, 6, 10] ```
#### `binary_search.py`
```python > python binary_search.py Recursive: 6 Iterative: 6 ```