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9

モンティー・ホールは選択しない！

2018/04/19 14:56

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -28,9 +28,18 @@
28
28
  boxes[next_select_box]
29
29
  end.to_f / count
30
30
 
31
+ monty_hall_rate = count.times.count do
32
+ select_box = boxes.keys.sample
33
+ open_box = (boxes.keys - [select_box])
34
+ .reject(&boxes.method(:[])).sample
35
+ next_select_box = (boxes.keys - [select_box, open_box]).first
36
+ boxes[next_select_box]
37
+ end.to_f / count
38
+
31
39
  printf("%.1f%%\n", sonomama_rate * 100)
32
40
  printf("%.1f%%\n", naosu_rate * 100)
33
41
  printf("%.1f%%\n", monty_rate * 100)
42
+ printf("%.1f%%\n", monty_hall_rate * 100)
34
43
  ```
35
44
 
36
45
  ```CoffeeScript
@@ -66,9 +75,21 @@
66
75
  boxes[next_selectBox]
67
76
  .length / count
68
77
 
78
+ montyHallRate = [1..count].filter ->
79
+ selectBox = sample(Object.keys(boxes))
80
+ openBox = sample(Object.keys(boxes)
81
+ .filter((box) -> box != selectBox)
82
+ .filter((box) -> !boxes[box]))
83
+ next_selectBox = Object.keys(boxes)
84
+ .filter((box) -> box != selectBox && box != openBox)
85
+ boxes[next_selectBox]
86
+ .length / count
87
+
88
+
69
89
  console.log "#{(sonomamaRate * 100).toFixed(1)}%"
70
90
  console.log "#{(naosuRate * 100).toFixed(1)}%"
71
91
  console.log "#{(montyRate * 100).toFixed(1)}%"
92
+ console.log "#{(montyHallRate * 100).toFixed(1)}%"
72
93
  ```
73
94
 
74
95
  ```Kotlin
@@ -97,19 +118,32 @@
97
118
 
98
119
  val montyRate = IntRange(1, count).count(fun(_: Int): Boolean {
99
120
  val selectBox = boxes.keys.shuffled().first()
100
- val open_box = boxes.keys
121
+ val openBox = boxes.keys
101
122
  .filterNot({ selectBox.equals(it) })
102
123
  .filterNot({ boxes.getOrDefault(it, false) })
103
124
  .shuffled().first()
104
125
  val nextSelectBox = boxes.keys
105
- .filterNot({ open_box.equals(it) })
126
+ .filterNot({ openBox.equals(it) })
106
127
  .shuffled().first()
107
128
  return boxes.getOrDefault(nextSelectBox, false)
108
129
  }).toDouble() / count
109
130
 
131
+ val montyHallRate = IntRange(1, count).count(fun(_: Int): Boolean {
132
+ val selectBox = boxes.keys.shuffled().first()
133
+ val openBox = boxes.keys
134
+ .filterNot({ selectBox.equals(it) })
135
+ .filterNot({ boxes.getOrDefault(it, false) })
136
+ .shuffled().first()
137
+ val nextSelectBox = boxes.keys
138
+ .filterNot({ selectBox.equals(it) || openBox.equals(it) })
139
+ .shuffled().first()
140
+ return boxes.getOrDefault(nextSelectBox, false)
141
+ }).toDouble() / count
142
+
110
143
  println("%.1f%%".format(sonomamaRate * 100))
111
144
  println("%.1f%%".format(naosuRate * 100))
112
145
  println("%.1f%%".format(montyRate * 100))
146
+ println("%.1f%%".format(montyHallRate * 100))
113
147
  }
114
148
  ```
115
149
  ※ 3番目のコードはKotlinです。Kotlinはシンタックス指定が対応していないっぽい。

8

最初Kotlinスクリプトで書いていたから外出ししていたけど、なんでトップにあんねん！とおもってmainの中に引っ込めた。

2018/04/19 14:55

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -74,39 +74,39 @@
74
74
  ```Kotlin
75
75
  import kotlin.ranges.IntRange
76
76
 
77
+ fun main(args: Array<String>) {
77
- val boxes = mapOf(
78
+ val boxes = mapOf(
78
- "a" to true,
79
+ "a" to true,
79
- "b" to false,
80
+ "b" to false,
80
- "c" to false)
81
+ "c" to false)
81
82
 
82
- val count = 100000 // 10万回
83
+ val count = 100000 // 10万回
83
84
 
84
- val sonomamaRate = IntRange(1, count).count(fun(_: Int): Boolean {
85
+ val sonomamaRate = IntRange(1, count).count(fun(_: Int): Boolean {
85
- val selectBox = boxes.keys.shuffled().first()
86
+ val selectBox = boxes.keys.shuffled().first()
86
- return boxes.getOrDefault(selectBox, false)
87
+ return boxes.getOrDefault(selectBox, false)
87
- }).toDouble() / count
88
+ }).toDouble() / count
88
89
 
89
- val naosuRate = IntRange(1, count).count(fun(_: Int): Boolean {
90
+ val naosuRate = IntRange(1, count).count(fun(_: Int): Boolean {
90
- val selectBox = boxes.keys.shuffled().first()
91
+ val selectBox = boxes.keys.shuffled().first()
91
- val nextSelectBox = boxes.keys
92
+ val nextSelectBox = boxes.keys
92
- .filterNot({ selectBox.equals(it) })
93
+ .filterNot({ selectBox.equals(it) })
93
- .shuffled().first()
94
+ .shuffled().first()
94
- return boxes.getOrDefault(nextSelectBox, false)
95
+ return boxes.getOrDefault(nextSelectBox, false)
95
- }).toDouble() / count
96
+ }).toDouble() / count
96
97
 
97
- val montyRate = IntRange(1, count).count(fun(_: Int): Boolean {
98
+ val montyRate = IntRange(1, count).count(fun(_: Int): Boolean {
98
- val selectBox = boxes.keys.shuffled().first()
99
+ val selectBox = boxes.keys.shuffled().first()
99
- val open_box = boxes.keys
100
+ val open_box = boxes.keys
100
- .filterNot({ selectBox.equals(it) })
101
+ .filterNot({ selectBox.equals(it) })
101
- .filterNot({ boxes.getOrDefault(it, false) })
102
+ .filterNot({ boxes.getOrDefault(it, false) })
102
- .shuffled().first()
103
+ .shuffled().first()
103
- val nextSelectBox = boxes.keys
104
+ val nextSelectBox = boxes.keys
104
- .filterNot({ open_box.equals(it) })
105
+ .filterNot({ open_box.equals(it) })
105
- .shuffled().first()
106
+ .shuffled().first()
106
- return boxes.getOrDefault(nextSelectBox, false)
107
+ return boxes.getOrDefault(nextSelectBox, false)
107
- }).toDouble() / count
108
+ }).toDouble() / count
108
109
 
109
- fun main(args: Array<String>) {
110
110
  println("%.1f%%".format(sonomamaRate * 100))
111
111
  println("%.1f%%".format(naosuRate * 100))
112
112
  println("%.1f%%".format(montyRate * 100))

7

上ってどこだ？

2018/04/19 14:43

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -112,4 +112,4 @@
112
112
  println("%.1f%%".format(montyRate * 100))
113
113
  }
114
114
  ```
115
- ※ 上のコードはKotlinです。Kotlinはシンタックス指定が対応していないっぽい。
115
+ ※ 3番目のコードはKotlinです。Kotlinはシンタックス指定が対応していないっぽい。

6

はじめてのKotlin

2018/04/19 14:20

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -111,4 +111,5 @@
111
111
  println("%.1f%%".format(naosuRate * 100))
112
112
  println("%.1f%%".format(montyRate * 100))
113
113
  }
114
- ```
114
+ ```
115
+ ※ 上のコードはKotlinです。Kotlinはシンタックス指定が対応していないっぽい。

5

Javaが抜けていたので追加した。

2018/04/19 14:19

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -69,4 +69,46 @@
69
69
  console.log "#{(sonomamaRate * 100).toFixed(1)}%"
70
70
  console.log "#{(naosuRate * 100).toFixed(1)}%"
71
71
  console.log "#{(montyRate * 100).toFixed(1)}%"
72
+ ```
73
+
74
+ ```Kotlin
75
+ import kotlin.ranges.IntRange
76
+
77
+ val boxes = mapOf(
78
+ "a" to true,
79
+ "b" to false,
80
+ "c" to false)
81
+
82
+ val count = 100000 // 10万回
83
+
84
+ val sonomamaRate = IntRange(1, count).count(fun(_: Int): Boolean {
85
+ val selectBox = boxes.keys.shuffled().first()
86
+ return boxes.getOrDefault(selectBox, false)
87
+ }).toDouble() / count
88
+
89
+ val naosuRate = IntRange(1, count).count(fun(_: Int): Boolean {
90
+ val selectBox = boxes.keys.shuffled().first()
91
+ val nextSelectBox = boxes.keys
92
+ .filterNot({ selectBox.equals(it) })
93
+ .shuffled().first()
94
+ return boxes.getOrDefault(nextSelectBox, false)
95
+ }).toDouble() / count
96
+
97
+ val montyRate = IntRange(1, count).count(fun(_: Int): Boolean {
98
+ val selectBox = boxes.keys.shuffled().first()
99
+ val open_box = boxes.keys
100
+ .filterNot({ selectBox.equals(it) })
101
+ .filterNot({ boxes.getOrDefault(it, false) })
102
+ .shuffled().first()
103
+ val nextSelectBox = boxes.keys
104
+ .filterNot({ open_box.equals(it) })
105
+ .shuffled().first()
106
+ return boxes.getOrDefault(nextSelectBox, false)
107
+ }).toDouble() / count
108
+
109
+ fun main(args: Array<String>) {
110
+ println("%.1f%%".format(sonomamaRate * 100))
111
+ println("%.1f%%".format(naosuRate * 100))
112
+ println("%.1f%%".format(montyRate * 100))
113
+ }
72
114
  ```

4

Rubyに引っ張られてスネークケースになっていたのでキャメルケースに直す

2018/04/19 14:18

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -44,29 +44,29 @@
44
44
  sample = (arr) ->
45
45
  arr[Math.floor(Math.random() * arr.length)]
46
46
 
47
- sonomama_rate = [0...count].filter ->
47
+ sonomamaRate = [1..count].filter ->
48
- select_box = sample(Object.keys(boxes))
48
+ selectBox = sample(Object.keys(boxes))
49
- boxes[select_box]
49
+ boxes[selectBox]
50
50
  .length / count
51
51
 
52
- naosu_rate = [0...count].filter ->
52
+ naosuRate = [1..count].filter ->
53
- select_box = sample(Object.keys(boxes))
53
+ selectBox = sample(Object.keys(boxes))
54
- next_select_box = sample(Object.keys(boxes)
54
+ next_selectBox = sample(Object.keys(boxes)
55
- .filter((box) -> box != select_box))
55
+ .filter((box) -> box != selectBox))
56
- boxes[next_select_box]
56
+ boxes[next_selectBox]
57
57
  .length / count
58
58
 
59
- monty_rate = [0...count].filter ->
59
+ montyRate = [1..count].filter ->
60
- select_box = sample(Object.keys(boxes))
60
+ selectBox = sample(Object.keys(boxes))
61
- open_box = sample(Object.keys(boxes)
61
+ openBox = sample(Object.keys(boxes)
62
- .filter((box) -> box != select_box)
62
+ .filter((box) -> box != selectBox)
63
63
  .filter((box) -> !boxes[box]))
64
- next_select_box = sample(Object.keys(boxes)
64
+ next_selectBox = sample(Object.keys(boxes)
65
- .filter((box) -> box != open_box))
65
+ .filter((box) -> box != openBox))
66
- boxes[next_select_box]
66
+ boxes[next_selectBox]
67
67
  .length / count
68
68
 
69
- console.log "#{(sonomama_rate * 100).toFixed(1)}%"
69
+ console.log "#{(sonomamaRate * 100).toFixed(1)}%"
70
- console.log "#{(naosu_rate * 100).toFixed(1)}%"
70
+ console.log "#{(naosuRate * 100).toFixed(1)}%"
71
- console.log "#{(monty_rate * 100).toFixed(1)}%"
71
+ console.log "#{(montyRate * 100).toFixed(1)}%"
72
72
  ```

3

JavaScriptのタグがあることに気付いた

2018/04/19 14:14

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -31,4 +31,42 @@
31
31
  printf("%.1f%%\n", sonomama_rate * 100)
32
32
  printf("%.1f%%\n", naosu_rate * 100)
33
33
  printf("%.1f%%\n", monty_rate * 100)
34
+ ```
35
+
36
+ ```CoffeeScript
37
+ boxes =
38
+ a: true
39
+ b: false
40
+ c: false
41
+
42
+ count = 100000 # 10万回
43
+
44
+ sample = (arr) ->
45
+ arr[Math.floor(Math.random() * arr.length)]
46
+
47
+ sonomama_rate = [0...count].filter ->
48
+ select_box = sample(Object.keys(boxes))
49
+ boxes[select_box]
50
+ .length / count
51
+
52
+ naosu_rate = [0...count].filter ->
53
+ select_box = sample(Object.keys(boxes))
54
+ next_select_box = sample(Object.keys(boxes)
55
+ .filter((box) -> box != select_box))
56
+ boxes[next_select_box]
57
+ .length / count
58
+
59
+ monty_rate = [0...count].filter ->
60
+ select_box = sample(Object.keys(boxes))
61
+ open_box = sample(Object.keys(boxes)
62
+ .filter((box) -> box != select_box)
63
+ .filter((box) -> !boxes[box]))
64
+ next_select_box = sample(Object.keys(boxes)
65
+ .filter((box) -> box != open_box))
66
+ boxes[next_select_box]
67
+ .length / count
68
+
69
+ console.log "#{(sonomama_rate * 100).toFixed(1)}%"
70
+ console.log "#{(naosu_rate * 100).toFixed(1)}%"
71
+ console.log "#{(monty_rate * 100).toFixed(1)}%"
34
72
  ```

2

rateは最大1で%にするときに100かけた方が綺麗になるような気がした。たぶん、木の精だけど。

2018/04/19 13:08

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -12,13 +12,13 @@
12
12
  sonomama_rate = count.times.count do
13
13
  select_box = boxes.keys.sample
14
14
  boxes[select_box]
15
- end.to_f / count * 100
15
+ end.to_f / count
16
16
 
17
17
  naosu_rate = count.times.count do
18
18
  select_box = boxes.keys.sample
19
19
  next_select_box = (boxes.keys - [select_box]).sample
20
20
  boxes[next_select_box]
21
- end.to_f / count * 100
21
+ end.to_f / count
22
22
 
23
23
  monty_rate = count.times.count do
24
24
  select_box = boxes.keys.sample
@@ -26,9 +26,9 @@
26
26
  .reject(&boxes.method(:[])).sample
27
27
  next_select_box = (boxes.keys - [open_box]).sample
28
28
  boxes[next_select_box]
29
- end.to_f / count * 100
29
+ end.to_f / count
30
30
 
31
- printf("%.1f%%\n", sonomama_rate)
31
+ printf("%.1f%%\n", sonomama_rate * 100)
32
- printf("%.1f%%\n", naosu_rate)
32
+ printf("%.1f%%\n", naosu_rate * 100)
33
- printf("%.1f%%\n", monty_rate)
33
+ printf("%.1f%%\n", monty_rate * 100)
34
34
  ```

1

sampleメソッドの方が良かった

2018/04/19 11:47

投稿

raccy
raccy

スコア21807

answer CHANGED
@@ -10,21 +10,21 @@
10
10
  count = 100_000 # 10万回
11
11
 
12
12
  sonomama_rate = count.times.count do
13
- select_box = boxes.keys.shuffle.first
13
+ select_box = boxes.keys.sample
14
14
  boxes[select_box]
15
15
  end.to_f / count * 100
16
16
 
17
17
  naosu_rate = count.times.count do
18
- select_box = boxes.keys.shuffle.first
18
+ select_box = boxes.keys.sample
19
- next_select_box = (boxes.keys - [select_box]).shuffle.first
19
+ next_select_box = (boxes.keys - [select_box]).sample
20
20
  boxes[next_select_box]
21
21
  end.to_f / count * 100
22
22
 
23
23
  monty_rate = count.times.count do
24
- select_box = boxes.keys.shuffle.first
24
+ select_box = boxes.keys.sample
25
25
  open_box = (boxes.keys - [select_box])
26
- .reject(&boxes.method(:[])).shuffle.first
26
+ .reject(&boxes.method(:[])).sample
27
- next_select_box = (boxes.keys - [open_box]).shuffle.first
27
+ next_select_box = (boxes.keys - [open_box]).sample
28
28
  boxes[next_select_box]
29
29
  end.to_f / count * 100
30
30