1154\. Day of the Year

Easy

Given a string `date` representing a [Gregorian calendar](https://en.wikipedia.org/wiki/Gregorian_calendar) date formatted as `YYYY-MM-DD`, return _the day number of the year_.

**Example 1:**

**Input:** date = "2019-01-09"

**Output:** 9

**Explanation:** Given date is the 9th day of the year in 2019.

**Example 2:**

**Input:** date = "2019-02-10"

**Output:** 41

**Constraints:**

*   `date.length == 10`
*   `date[4] == date[7] == '-'`, and all other `date[i]`'s are digits
*   `date` represents a calendar date between Jan 1<sup>st</sup>, 1900 and Dec 31<sup>th</sup>, 2019.