This commit is contained in:
Stephen McQuay 2018-05-04 21:45:21 -07:00
commit 75f80ae39f
Signed by: sm
GPG Key ID: C383C74875475AC8
3 changed files with 79 additions and 0 deletions

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LICENSE Normal file
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MIT License
Copyright (c) 2018 Stephen McQuay
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

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README.md Normal file
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# smerge
This answers an interview question

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main.go Normal file
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package main
import (
"fmt"
"math/rand"
"sort"
"sync"
"time"
)
func main() {
for i := range merge(source(5), source(10), source(20)) {
fmt.Printf("%20d\n", i)
}
}
func source(c int) <-chan int {
out := make(chan int)
go func() {
vals := make([]int, c)
src := rand.New(rand.NewSource(time.Now().UnixNano()))
for i := 0; i < c; i++ {
vals[i] = src.Int()
}
sort.Ints(vals)
for _, i := range vals {
out <- i
}
close(out)
}()
return out
}
func merge(cs ...<-chan int) <-chan int {
wg := sync.WaitGroup{}
out := make(chan int)
output := func(c <-chan int) {
for n := range c {
out <- n
}
wg.Done()
}
wg.Add(len(cs))
for _, c := range cs {
go output(c)
}
go func() {
wg.Wait()
close(out)
}()
return out
}