sort_example.go

package main

import (
	"fmt"
	"time"
	"sort"
	"math/rand"
)


func sortInt() {
	rand.Seed(time.Now().UTC().UnixNano())
	count := 30
	maxInt := 10000
	arr := make([]int , count)

	for i, _ := range arr {
		arr[i] = rand.Int() % int(maxInt)
	}

	fmt.Println("Sort this array : ", arr)
	sort.Sort(sort.IntSlice(arr))
	fmt.Println("Sorted result   : ", arr)
	sort.Sort(sort.Reverse(sort.IntSlice(arr)))
	fmt.Println("Reversed result : ", arr)
}

func sortRankings(){
	rankings := []Ranking {
		{"88154420822432544", 1436520192, 13960},
		{"91670176688136577", 1440799941, 13080},
		{"88180751521592112", 1435637878, 14280},
		{"88144324860977520", 1437278775, 13560},
		{"93797540915256451", 1435889873, 14200},
		{"88249875880704624", 1438226613, 11960},
		{"88192601275706464", 1436694190, 13320},
		{"88148115536237952", 1436450939, 13600},
		{"89047353485705664", 1435654249, 12760},
		{"88182263314045056", 1436586635, 13320},
		{"88193534078563601", 1438176365, 16600},
		{"88256711722920353", 1437136853, 8920},
		{"89852877819675984", 1436684270, 12680},
		{"93594773313085234", 1437634370, 8480},
		{"90289273133727025", 1436351481, 10800},
		{"92150085612088915", 1440609977, 12720},
		{"91211930152797040", 1438076721, 10920},
		{"88309448624594448", 1438057506, 10440},
		{"88406950494717233", 1436508922, 11000},
		{"93176928270204371", 1437293064, 10440},
		{"88056851903088048", 1436338570, 10440},
		{"93691000129391522", 1436618165, 12560},
		{"88675559501659840", 1438230885, 9800},
	}

	sort.Sort(RankingSlice(rankings))
	fmt.Println(rankings)
}

// Ranking struct
type Ranking struct {
	kakaoid string
	written_date int
	score int
}

func (ranking Ranking) String () string {
	return fmt.Sprintf("kakaoid %s score %d written_date %d\n", ranking.kakaoid, ranking.score, ranking.written_date)
}

// RankingSlice----------------------------------------------START
type RankingSlice []Ranking
func (arr RankingSlice) Len() int {
	return len(arr)
}

// j 인덱스를 가진녀석이 i 앞으로 와야하는지 말아야하는지를 판단하는 함수
func (arr RankingSlice) Less(i, j int) bool {
	if arr[i].score == arr[j].score {
		return arr[i].written_date > arr[j].written_date
	} else {
		return arr[i].score > arr[j].score
	}
}

func (arr RankingSlice) Swap(i, j int) {
	arr[i], arr[j] = arr[j], arr[i]
}
//RankingSlice----------------------------------------------END

func main() {
	sortInt()
	sortRankings()

}