#725275 (Go) No.1095 Smallest Kadomatsu Subsequence

• 問題: No.1095 Smallest Kadomatsu Subsequence
• ユーザー: 小野寺健
• 提出日時: 2021-12-20 08:54:31
• 言語: Go (1.22.1)
• 結果: AC
• 実行時間: 319 ms / 2,000 ms
• コード長: 1,922 bytes
• コンパイル時間: 14,896 ms
• コンパイル使用メモリ: 230,912 KB
• 実行使用メモリ: 16,000 KB
• 最終ジャッジ日時: 2024-09-15 15:13:44
• 合計ジャッジ時間: 19,864 ms
• ジャッジサーバーID （参考情報）: judge6 / judge2

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 5,248 KB
testcase_01	AC	1 ms; 5,248 KB
testcase_02	AC	1 ms; 5,376 KB
testcase_03	AC	1 ms; 5,376 KB
testcase_04	AC	1 ms; 5,376 KB
testcase_05	AC	1 ms; 5,376 KB
testcase_06	AC	2 ms; 5,376 KB
testcase_07	AC	2 ms; 5,376 KB
testcase_08	AC	2 ms; 5,376 KB
testcase_09	AC	2 ms; 5,376 KB
testcase_10	AC	2 ms; 5,376 KB
testcase_11	AC	1 ms; 5,376 KB
testcase_12	AC	1 ms; 5,376 KB
testcase_13	AC	13 ms; 5,376 KB
testcase_14	AC	13 ms; 5,376 KB
testcase_15	AC	13 ms; 5,376 KB
testcase_16	AC	13 ms; 5,376 KB
testcase_17	AC	13 ms; 5,376 KB
testcase_18	AC	13 ms; 5,376 KB
testcase_19	AC	13 ms; 5,376 KB
testcase_20	AC	13 ms; 5,376 KB
testcase_21	AC	13 ms; 5,376 KB
testcase_22	AC	13 ms; 5,376 KB
testcase_23	AC	311 ms; 16,000 KB
testcase_24	AC	319 ms; 16,000 KB
testcase_25	AC	312 ms; 16,000 KB
testcase_26	AC	307 ms; 16,000 KB
testcase_27	AC	310 ms; 16,000 KB
testcase_28	AC	198 ms; 16,000 KB
testcase_29	AC	201 ms; 16,000 KB
testcase_30	AC	252 ms; 16,000 KB
testcase_31	AC	254 ms; 16,000 KB
testcase_32	AC	251 ms; 16,000 KB

ソースコード

package main

import (
	"fmt"
	"bufio"
	"os"
	"sort"
	"math"
)

func Min(a, b int) int {
	if a < b {
		return a
	} else {
		return b
	}
}

type SegmentTree struct {
	n int
	tree []int
}

func newSegmentTree(n int) *SegmentTree{
	sp := new(SegmentTree)
	sp.n = 1
	for sp.n < n {
		sp.n *= 2
	}
	sp.tree = make([]int, 2*sp.n)
	for i := 0; i < 2*sp.n; i++ {
		sp.tree[i] = math.MaxInt64
	}
	return sp
}

func (this *SegmentTree) set(idx, x int) {
	idx += this.n
	this.tree[idx] = x
	for idx > 0 {
		idx >>= 1
		this.tree[idx] = Min(this.tree[2 * idx], this.tree[2 * idx + 1])
	}
}

func (this *SegmentTree) query(lt, rt int) int {
	lt += this.n
	rt += this.n
	vl, vr := math.MaxInt64, math.MaxInt64
	for rt - lt > 0 {
		if lt & 1 != 0 {
			vl = Min(vl, this.tree[lt])
			lt++
		}
		if rt & 1 != 0 {
			rt--
			vr = Min(this.tree[rt], vr)
		}
		lt >>= 1
		rt >>= 1
	}
	return Min(vl, vr)
}

func main() {
	r := bufio.NewReader(os.Stdin)
	w := bufio.NewWriter(os.Stdout)
	defer w.Flush()
	var N int
	fmt.Fscan(r, &N)
	A := make([][2]int, N)
	for i := 0; i < N; i++ {
		var x int
		fmt.Fscan(r, &x)
		A[i] = [2]int{x, i}
	}
	sort.Slice(A, 
		func(i, j int) bool {
			if A[i][0] < A[j][0] {
				return true
			} else if A[i][0] > A[j][0] {
				return false
			} else {
				return A[i][1] < A[j][1]
			}
		})
	res := math.MaxInt64
	st1 := newSegmentTree(N)
	for i := 0; i < N; i++ {
		a, idx := A[i][0], A[i][1]
		st1.set(idx, a)
		lt := st1.query(0, idx)
		rt := st1.query(idx + 1, N)
		if lt == math.MaxInt64 || rt == math.MaxInt64 {
			continue
		}
		res = Min(res, lt + rt + a)
	}
	st2 := newSegmentTree(N)
	for i := N-1; i >= 0; i-- {
		a, idx := A[i][0], A[i][1]
		st2.set(idx, a)
		lt := st2.query(0, idx)
		rt := st2.query(idx + 1, N)
		if lt == math.MaxInt64 || rt == math.MaxInt64 {
			continue
		}
		res = Min(res, lt + rt + a)		
	}
	if res == math.MaxInt64 {
		fmt.Fprintln(w, -1)
	} else {
		fmt.Fprintln(w, res)
	}
}