結果

問題 No.5007 Steiner Space Travel
ユーザー ID 21712
提出日時 2025-01-30 14:50:14
言語 Go
(1.23.4)
結果
AC  
実行時間 833 ms / 1,000 ms
コード長 3,546 bytes
コンパイル時間 12,191 ms
コンパイル使用メモリ 248,796 KB
実行使用メモリ 8,300 KB
スコア 8,313,692
最終ジャッジ日時 2025-01-30 14:50:56
合計ジャッジ時間 37,270 ms
ジャッジサーバーID
（参考情報） 		judge2 / judge1
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ファイルパターン 結果
other AC * 30
権限があれば一括ダウンロードができます

ソースコード

diff # 

package main

import . "fmt"
import "math/rand"

const ALPHA = 5

func dist(a,b []int, i int, c,d []int, j int) int {
	dx := a[i] - c[j]
	dy := b[i] - d[j]
	return dx*dx + dy*dy
}

func main() {
	var n, m int
	Scan(&n, &m)
	a := make([]int, n)
	b := make([]int, n)
	for i := range a {
		Scan(&a[i],&b[i])
	}
	c := make([]int, m)
	d := make([]int, m)

	path := make([][][]int, n+m)

	p := []int{0}
	for i := 0; i < n; i++ {
		p = append(p, (i+1)%n)
	}
	
	calc := func(p []int) int {
		sc := 0
		for i := 0; i < n; i++ {
			sc += path[p[i]][p[i+1]][0]
		}
		return sc
	}
	
	bestSc := int(1e9)
	bestC := make([]int, m)
	bestD := make([]int, m)
	bestT := make([]int, 0, 5000)
	bestR := make([]int, 0, 5000)
	
	var add func(i, j int)
	add = func(i, j int) {
		rt := path[i][j]
		if rt[1] == j {
			if j < n {
				bestT = append(bestT, 1)
				bestR = append(bestR, j+1)
			} else {
				bestT = append(bestT, 2)
				bestR = append(bestR, j-n+1)
			}
			return
		}
		add(i, rt[1])
		add(rt[1], j)
	}
	
	for q := 0; q < 50; q++ {
		
		for i := range c {
			if i < m/2 {
				c[i] = (i/3+1)*250
				d[i] = (i%3+1)*250
			} else {
				c[i] = ((i+1)/3+1)*250
				d[i] = ((i+1)%3+1)*250
			}
			
			if q > 0 {
				c[i] += (rand.Intn(100+1)-50)*(rand.Intn(3)+1)
				d[i] += (rand.Intn(100+1)-50)*(rand.Intn(3)+1)
			}
		}
		
		rand.Shuffle(n-1, func(i, j int) {
			p[i+1],p[j+1] = p[j+1],p[i+1]
		})
		
		for i := range path {
			path[i] = make([][]int, n+m)
			for j := range path[i] {
				switch {
					case i == j:
						path[i][j] = []int{ 0, j }
					case i < n && j < n:
						path[i][j] = []int{
							ALPHA*ALPHA*dist(a,b,i,a,b,j),
							j,
						}
					case i < n:
						path[i][j] = []int{
							ALPHA*dist(a,b,i,c,d,j-n),
							j,
						}
					case j < n:
						path[i][j] = []int{
							ALPHA*dist(c,d,i-n,a,b,j),
							j,
						}
					default:
						path[i][j] = []int{
							dist(c,d,i-n,c,d,j-n),
							j,
						}
				}
			}
		}
		
		for i := 0; i < n+m; i++ {
			for j := 0; j < n+m; j++ {
				if i == j {
					continue
				}
				for k := 0; k < n+m; k++ {
					if i==k || j==k {
						continue
					}
					if x := path[i][k][0]+path[k][j][0]; x < path[i][j][0] {
						path[i][j][0] = x
						path[i][j][1] = k
					}
				}
			}
		}

		for cc, changed := 0, true; changed && cc < 20; cc++ {
			changed = false
			// 2-opt ?
			for i := 1; i < n; i++ {
				for j := i+1; j < n; j++ {
					s0 := path[p[i-1]][p[i]][0] +
						path[p[j]][p[j+1]][0]
					s1 := path[p[i-1]][p[j]][0] +
						path[p[i]][p[j+1]][0]
					if s1 < s0 {
						for f,e := i,j; f < e; f,e=f+1,e-1 {
							p[f],p[e] = p[e],p[f]
						}
						changed = true
					}
				}
			}
			// 3-opt ?
			for i := 1; i < n; i++ {
				for j := i+1; j < n; j++ {
					for k := j+2; k < n; k++ {
						s0 := path[p[i-1]][p[i]][0] +
							path[p[j]][p[j+1]][0] +
							path[p[k]][p[k+1]][0]
						s1 := path[p[i-1]][p[j]][0] +
							path[p[i]][p[k]][0] +
							path[p[j+1]][p[k+1]][0]
						if s1 < s0 {
							for f,e := i,j; f < e; f,e=f+1,e-1 {
								p[f],p[e] = p[e],p[f]
							}
							for f,e := j+1,k; f < e; f,e=f+1,e-1 {
								p[f],p[e] = p[e],p[f]
							}
							changed = true
						}
					}
				}
			}
		}
		
		if sc := calc(p); sc < bestSc {
			bestSc = sc
			copy(bestC, c)
			copy(bestD, d)
			bestT = append(bestT[:0], 1)
			bestR = append(bestR[:0], 1)
			for i := 0; i < n; i++ {
				add(p[i], p[i+1])
			}
		}

	}

	for i := range bestC {
		Println(bestC[i], bestD[i])
	}
	Println(len(bestT))
	for i := range bestT {
		Println(bestT[i], bestR[i])
	}
	
}
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