我有一個關于切片、計數器、時間以及 Go 中令人費解的合并和排序的一般性問題。我從在線實踐練習中編寫了一個小程序來了解 Go，我很困惑為什么我編寫的解決方案會出錯。代碼只是兩個計數器切片，它們是按時間排序的，我決定嘗試合并它，然后再次按與計數對應的時間排序。我已經完成了其余的代碼，但合并讓我感到困惑。將提供代碼片段供您閱讀。package mainimport ( "fmt" "time")/*Given Counter slices that are sorted by Time, merge the slices into one slice.Make sure that counters with the same Time are merged and the Count is increased.E.g:A = [{Time: 0, Count: 5}, {Time:1, Count: 3}, {Time: 4, Count 7}]B = [{Time: 1, Count: 9}, {Time:2, Count: 1}, {Time: 3, Count 3}]merge(A, B) ==>[{Time: 0, Count: 5}, {Time: 1: Count: 12}, {Time: 2, Count 1}, {Time: 3, Count: 3}, {Time: 4: Count: 7}]Explain the efficiency of your merging.*/type Counter struct { Time time.Time Count uint64}var ( A = []Counter{ {Time: time.Unix(0, 0), Count: 5}, {Time: time.Unix(0, 1), Count: 3}, {Time: time.Unix(0, 4), Count: 7}, } B = []Counter{ {Time: time.Unix(0, 0), Count: 5}, {Time: time.Unix(0, 1), Count: 12}, {Time: time.Unix(0, 2), Count: 1}, {Time: time.Unix(0, 3), Count: 3}, {Time: time.Unix(0, 4), Count: 7}, })func merge(a, b []Counter) []Counter { // Insert your code here res1 := append(a) <--- ERROR? res2 := append(b) <--- ERROR? return nil}func main() { AB := merge(A, B) for _, c := range AB { fmt.Println(c) }}
1 回答
精慕HU
TA貢獻1845條經驗 獲得超8個贊
要解決有關附加和排序數組的問題，您只需將一個數組的片段附加到另一個數組，如下所示：
result := append(a, b...)
要根據 unix time 等內部結構類型對數組進行排序，最好的辦法是創建切片的自定義類型并實現 sort.Interface 的方法。
示例是：
type ByTime []Counter
func (c ByTime) Len() int { return len(c) }
func (c ByTime) Swap(i, j int) { c[i], c[j] = c[j], c[i] }
func (c ByTime) Less(i, j int) bool { return c[i].Time.Before(c[j].Time) }
然后只打電話
sort.Sort(ByTime(result))
完整示例： https: //play.golang.org/p/L9_aPRlQsss
但請注意，我并沒有解決您的編碼練習如何基于內部指標合并兩個數組，僅將一個附加到另一個。你需要在你的家庭作業中做一些工作；-) 這仍然會產生排序的（不是元素合并的）切片：
{1970-01-01 00:00:00 +0000 UTC 5}
{1970-01-01 00:00:00.000000001 +0000 UTC 3}
{1970-01-01 00:00:00.000000001 +0000 UTC 9}
{1970-01-01 00:00:00.000000002 +0000 UTC 1}
{1970-01-01 00:00:00.000000003 +0000 UTC 3}
{1970-01-01 00:00:00.000000004 +0000 UTC 7}
- 1 回答
- 0 關注
- 118 瀏覽
添加回答
舉報
0/150
提交
取消