## Description

Count how many occurrence of number **1** between 2 numbers \$[a, b]\$.

For example from 1 to 100 it should be 21:

**1**,  **11**,  **1**2, **1**3, **1**4, **1**5, **1**6, **1**7, **1**8, **1**9, 2**1**, 3**1**, 4**1**, 5**1**, 6**1**, 7**1**, 8**1**, 9**1**

The number **1** is repeated 20 times.

## Rules

1. Each number in the input list is guaranteed is an integer in the range \$0 \leq a \leq b < 2^{32}\$.
2. The shortest answer in bytes wins.


## Test cases

    [1,100] -> 20
    [11,200] -> 138
    [123,678] -> 182

## Other

Here is my code using bash

```
eval echo {$1..$2}|grep -o 1|wc -l
```