Some folks go on vacation around the Easter holidays, so it would be nice to know when Easter happens in the years ahead. I had this as a Python snippet in my "oldies, but goodies" file and translated it to Go. It was actually quite easy in this case, and a good IDE like LiteIDE helped a lot.

```
// easter_date2.go
//
// Easter date for a given year in the Gregorian calendar
// (1583 and onward) using the Gauss Algorithm
//
// fairly straight translation from one of my Python snippets
//
// tested with Go version 1.4.2 by vegaseat 2may2015
package main
import "fmt"
// Gauss algorithm to calculate the date of Easter in a given year
// returns day, month, year as integers
func getEaster2(year int) (int, int, int) {
// don't go below start of Gregorian calendar
if year < 1583 {
year = 1583
}
// for type (by inference) and value assignment use :=
// shorthand for var month int = 3
month := 3
// determine the Golden number
golden := (year % 19) + 1
// determine the century number
century := year/100 + 1
// correct for the years that are not leap years
xx := (3*century)/4 - 12
// moon correction
yy := (8*century+5)/25 - 5
// find Sunday
zz := (5*year)/4 - xx - 10
// determine epact
// age of moon on January 1st of that year
// (follows a cycle of 19 years)
ee := (11*golden + 20 + yy - xx) % 30
if ee == 24 {
ee += 1
}
if (ee == 25) && (golden > 11) {
ee += 1
}
// get the full moon
moon := 44 - ee
if moon < 21 {
moon += 30
}
// up to Sunday
day := (moon + 7) - ((zz + moon) % 7)
// possibly up a month in easter_date
if day > 31 {
day -= 31
month = 4
}
return day, month, year
}
func main() {
fmt.Println("Easter date of a given year:")
for jahr := 2011; jahr <= 2018; jahr++ {
day, month, year := getEaster2(jahr)
fmt.Printf("Easter %d is on %v/%v/%v\n",
year, month, day, year)
}
}
/*
Easter date of a given year:
Easter 2011 is on 4/24/2011
Easter 2012 is on 4/8/2012
Easter 2013 is on 3/31/2013
Easter 2014 is on 4/20/2014
Easter 2015 is on 4/5/2015
Easter 2016 is on 3/27/2016
Easter 2017 is on 4/16/2017
Easter 2018 is on 4/1/2018
*/
```

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