# Leetcode: Day of the Year

Day of the Year

Similar Problems:

Given a string date representing a 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
```

Example 3:

```Input: date = "2003-03-01"
Output: 60
```

Example 4:

```Input: date = "2004-03-01"
Output: 61
```

Constraints:

• date.length == 10
• date[4] `= date[7] =` ‘-‘, and all other date[i]’s are digits
• date represents a calendar date between Jan 1st, 1900 and Dec 31, 2019.

Github: code.dennyzhang.com

Credits To: leetcode.com

Leave me comments, if you have better ways to solve.

• Solution:
```// Blog link: https://code.dennyzhang.com/ordinal-number-of-date
// Basic Ideas: array
//
// Complexity: Time O(1), Space O(1)
import ("strings"
"strconv")
func dayOfYear(date string) int {
items := strings.Split(date, "-")
year, _ := strconv.Atoi(items[0])
month, _ := strconv.Atoi(items[1])
day, _ := strconv.Atoi(items[2])

res := day

l := []int{0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
if (year%4 ==0 && year%100!=0) || (year%400 == 0) {
l[2] = 29
}
for i:=1; i<month; i++ {
res += l[i]
}
return res
}
```

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