結果
| 問題 | No.20 砂漠のオアシス |
| ユーザー |
 maguroguma
|
| 提出日時 | 2020-01-04 22:35:53 |
| 言語 | Go (1.22.1) |
| 結果 |
AC
|
| 実行時間 | 45 ms / 5,000 ms |
| コード長 | 9,312 bytes |
| コンパイル時間 | 10,501 ms |
| コンパイル使用メモリ | 219,976 KB |
| 実行使用メモリ | 10,112 KB |
| 最終ジャッジ日時 | 2024-05-02 08:55:01 |
| 合計ジャッジ時間 | 11,423 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge1 |
（要ログイン）
テストケース
テストケース表示| 入力 | 結果 | 実行時間 実行使用メモリ |
|---|---|---|
| testcase_00 | AC | 2 ms
6,816 KB |
| testcase_01 | AC | 2 ms
5,248 KB |
| testcase_02 | AC | 1 ms
6,816 KB |
| testcase_03 | AC | 3 ms
5,376 KB |
| testcase_04 | AC | 3 ms
5,376 KB |
| testcase_05 | AC | 29 ms
8,576 KB |
| testcase_06 | AC | 45 ms
10,112 KB |
| testcase_07 | AC | 43 ms
10,112 KB |
| testcase_08 | AC | 31 ms
8,576 KB |
| testcase_09 | AC | 43 ms
10,112 KB |
| testcase_10 | AC | 1 ms
5,376 KB |
| testcase_11 | AC | 2 ms
5,376 KB |
| testcase_12 | AC | 3 ms
5,376 KB |
| testcase_13 | AC | 4 ms
5,376 KB |
| testcase_14 | AC | 6 ms
5,376 KB |
| testcase_15 | AC | 5 ms
5,376 KB |
| testcase_16 | AC | 8 ms
5,376 KB |
| testcase_17 | AC | 7 ms
5,632 KB |
| testcase_18 | AC | 8 ms
5,376 KB |
| testcase_19 | AC | 9 ms
5,376 KB |
| testcase_20 | AC | 2 ms
5,376 KB |
ソースコード
package main
import (
"bufio"
"container/heap"
"errors"
"fmt"
"io"
"math"
"os"
"strconv"
)
/*********** I/O ***********/
var (
// ReadString returns a WORD string.
ReadString func() string
stdout *bufio.Writer
)
func init() {
ReadString = newReadString(os.Stdin)
stdout = bufio.NewWriter(os.Stdout)
}
func newReadString(ior io.Reader) func() string {
r := bufio.NewScanner(ior)
// r.Buffer(make([]byte, 1024), int(1e+11)) // for AtCoder
r.Buffer(make([]byte, 1024), int(1e+9)) // for Codeforces
// Split sets the split function for the Scanner. The default split function is ScanLines.
// Split panics if it is called after scanning has started.
r.Split(bufio.ScanWords)
return func() string {
if !r.Scan() {
panic("Scan failed")
}
return r.Text()
}
}
// ReadInt returns an integer.
func ReadInt() int {
return int(readInt64())
}
func ReadInt2() (int, int) {
return int(readInt64()), int(readInt64())
}
func ReadInt3() (int, int, int) {
return int(readInt64()), int(readInt64()), int(readInt64())
}
func ReadInt4() (int, int, int, int) {
return int(readInt64()), int(readInt64()), int(readInt64()), int(readInt64())
}
// ReadInt64 returns as integer as int64.
func ReadInt64() int64 {
return readInt64()
}
func ReadInt64_2() (int64, int64) {
return readInt64(), readInt64()
}
func ReadInt64_3() (int64, int64, int64) {
return readInt64(), readInt64(), readInt64()
}
func ReadInt64_4() (int64, int64, int64, int64) {
return readInt64(), readInt64(), readInt64(), readInt64()
}
func readInt64() int64 {
i, err := strconv.ParseInt(ReadString(), 0, 64)
if err != nil {
panic(err.Error())
}
return i
}
// ReadIntSlice returns an integer slice that has n integers.
func ReadIntSlice(n int) []int {
b := make([]int, n)
for i := 0; i < n; i++ {
b[i] = ReadInt()
}
return b
}
// ReadInt64Slice returns as int64 slice that has n integers.
func ReadInt64Slice(n int) []int64 {
b := make([]int64, n)
for i := 0; i < n; i++ {
b[i] = ReadInt64()
}
return b
}
// ReadFloat64 returns an float64.
func ReadFloat64() float64 {
return float64(readFloat64())
}
func readFloat64() float64 {
f, err := strconv.ParseFloat(ReadString(), 64)
if err != nil {
panic(err.Error())
}
return f
}
// ReadFloatSlice returns an float64 slice that has n float64.
func ReadFloat64Slice(n int) []float64 {
b := make([]float64, n)
for i := 0; i < n; i++ {
b[i] = ReadFloat64()
}
return b
}
// ReadRuneSlice returns a rune slice.
func ReadRuneSlice() []rune {
return []rune(ReadString())
}
/*********** Debugging ***********/
// ZeroPaddingRuneSlice returns binary expressions of integer n with zero padding.
// For debugging use.
func ZeroPaddingRuneSlice(n, digitsNum int) []rune {
sn := fmt.Sprintf("%b", n)
residualLength := digitsNum - len(sn)
if residualLength <= 0 {
return []rune(sn)
}
zeros := make([]rune, residualLength)
for i := 0; i < len(zeros); i++ {
zeros[i] = '0'
}
res := []rune{}
res = append(res, zeros...)
res = append(res, []rune(sn)...)
return res
}
// Strtoi is a wrapper of strconv.Atoi().
// If strconv.Atoi() returns an error, Strtoi calls panic.
func Strtoi(s string) int {
if i, err := strconv.Atoi(s); err != nil {
panic(errors.New("[argument error]: Strtoi only accepts integer string"))
} else {
return i
}
}
// PrintIntsLine returns integers string delimited by a space.
func PrintIntsLine(A ...int) string {
res := []rune{}
for i := 0; i < len(A); i++ {
str := strconv.Itoa(A[i])
res = append(res, []rune(str)...)
if i != len(A)-1 {
res = append(res, ' ')
}
}
return string(res)
}
// PrintIntsLine returns integers string delimited by a space.
func PrintInts64Line(A ...int64) string {
res := []rune{}
for i := 0; i < len(A); i++ {
str := strconv.FormatInt(A[i], 10) // 64bit int version
res = append(res, []rune(str)...)
if i != len(A)-1 {
res = append(res, ' ')
}
}
return string(res)
}
// PrintDebug is wrapper of fmt.Fprintf(os.Stderr, format, a...)
func PrintDebug(format string, a ...interface{}) {
fmt.Fprintf(os.Stderr, format, a...)
}
/********** FAU standard libraries **********/
//fmt.Sprintf("%b\n", 255) // binary expression
/********** I/O usage **********/
//str := ReadString()
//i := ReadInt()
//X := ReadIntSlice(n)
//S := ReadRuneSlice()
//a := ReadFloat64()
//A := ReadFloat64Slice(n)
//str := ZeroPaddingRuneSlice(num, 32)
//str := PrintIntsLine(X...)
/*
ASCII code
ASCII 10進数 ASCII 10進数 ASCII 10進数
! 33 " 34 # 35
$ 36 % 37 & 38
' 39 ( 40 ) 41
* 42 + 43 , 44
- 45 . 46 / 47
0 48 1 49 2 50
3 51 4 52 5 53
6 54 7 55 8 56
9 57 : 58 ; 59
< 60 = 61 > 62
? 63 @ 64 A 65
B 66 C 67 D 68
E 69 F 70 G 71
H 72 I 73 J 74
K 75 L 76 M 77
N 78 O 79 P 80
Q 81 R 82 S 83
T 84 U 85 V 86
W 87 X 88 Y 89
Z 90 [ 91 \ 92
] 93 ^ 94 _ 95
` 96 a 97 b 98
c 99 d 100 e 101
f 102 g 103 h 104
i 105 j 106 k 107
l 108 m 109 n 110
o 111 p 112 q 113
r 114 s 115 t 116
u 117 v 118 w 119
x 120 y 121 z 122
{ 123 | 124 } 125
~ 126 127
*/
/*******************************************************************/
const (
// General purpose
MOD = 1000000000 + 7
ALPHABET_NUM = 26
INF_INT64 = math.MaxInt64
INF_BIT60 = 1 << 60
INF_INT32 = math.MaxInt32
INF_BIT30 = 1 << 30
NIL = -1
// for dijkstra, prim, and so on
WHITE = 0
GRAY = 1
BLACK = 2
)
var n, v int
var ox, oy int
var L [][]int
func main() {
n, v, ox, oy = ReadInt4()
for i := 0; i < n; i++ {
row := ReadIntSlice(n)
L = append(L, row)
}
for i := 0; i < n; i++ {
for j := 0; j < n; j++ {
cid := i*n + j
// LRUDの順で辺の有無をチェック
if j-1 >= 0 {
nid := i*n + (j - 1)
G[cid] = append(G[cid], Edge{to: nid, cost: L[i][j-1]})
}
if j+1 < n {
nid := i*n + (j + 1)
G[cid] = append(G[cid], Edge{to: nid, cost: L[i][j+1]})
}
if i+1 < n {
nid := (i+1)*n + j
G[cid] = append(G[cid], Edge{to: nid, cost: L[i+1][j]})
}
if i-1 >= 0 {
nid := (i-1)*n + j
G[cid] = append(G[cid], Edge{to: nid, cost: L[i-1][j]})
}
}
}
// オアシスなしでダイクストラ
dp := dijkstra(0)
PrintDebug("%v\n", dp[:n*n])
if dp[n*n-1] < v {
fmt.Println("YES")
return
}
// オアシスがある場合は、そこを経由してダイクストラ
if ox == 0 && oy == 0 {
fmt.Println("NO")
return
}
ox--
oy--
vv := v - dp[n*oy+ox]
if vv <= 0 {
fmt.Println("NO")
return
}
vv *= 2
dp = dijkstra(n*oy + ox)
if dp[n*n-1] < vv {
fmt.Println("YES")
return
}
fmt.Println("NO")
}
const NUM = 40000 + 5
func dijkstra(sid int) []int {
dp, colors, parents := make([]int, NUM), make([]int, NUM), make([]int, NUM)
for i := 0; i < NUM; i++ {
dp[i], colors[i], parents[i] = INF_BIT30, WHITE, NIL
}
dp[sid], colors[sid], parents[sid] = 0, GRAY, NIL
temp := make(VertexPQ, 0, 100000+1)
pq := &temp
heap.Init(pq)
heap.Push(pq, &Vertex{pri: 0, id: sid})
for pq.Len() > 0 {
cv := heap.Pop(pq).(*Vertex)
colors[cv.id] = BLACK
if dp[cv.id] < cv.pri {
continue
}
for _, e := range G[cv.id] {
if colors[e.to] == BLACK {
continue
}
if dp[e.to] > dp[cv.id]+e.cost {
dp[e.to] = dp[cv.id] + e.cost
colors[e.to] = GRAY
parents[e.to] = cv.id
heap.Push(pq, &Vertex{pri: dp[e.to], id: e.to})
}
}
}
return dp
}
var G [NUM][]Edge
type Edge struct {
to, cost int
}
type Vertex struct {
pri int
id int
}
type VertexPQ []*Vertex
func (pq VertexPQ) Len() int { return len(pq) }
func (pq VertexPQ) Less(i, j int) bool { return pq[i].pri < pq[j].pri } // <: ASC, >: DESC
func (pq VertexPQ) Swap(i, j int) {
pq[i], pq[j] = pq[j], pq[i]
}
func (pq *VertexPQ) Push(x interface{}) {
item := x.(*Vertex)
*pq = append(*pq, item)
}
func (pq *VertexPQ) Pop() interface{} {
old := *pq
n := len(old)
item := old[n-1]
*pq = old[0 : n-1]
return item
}
// how to use
// temp := make(VertexPQ, 0, 100000+1)
// pq := &temp
// heap.Init(pq)
// heap.Push(pq, &Vertex{pri: intValue})
// popped := heap.Pop(pq).(*Vertex)
/*
- まずは全探索を検討しましょう
- MODは最後にとりましたか？
- ループを抜けた後も処理が必要じゃありませんか？
- 和・積・あまりを求められたらint64が必要ではありませんか？
- いきなりオーバーフローはしていませんか？
- MOD取る系はint64必須ですよ？
*/
/*******************************************************************/