A Bouncy number is any non-negative integer that is neither increasing nor decreasing. An increasing number is any non-negative integer in which when going from left to right, the current digit is greater than or equal to the previous digit. For example, 469. A decreasing number is any non-negative integer in which when going from left to right, the current digit is less than or equal to the previous digit. Ex. 821 A Bouncy number is that number which is neither increasing or decreasing. Ex. 104, 978, 1132. List the first 10000 Bouncy numbers.
📌 Challenge Details and Links
ExcelBI Excel Challenge Number: 466
Challenge Difficulty: ⭐️⭐️⭐️
📥Download Sample File
📥Link to the solutions on LinkedIn
Solving the challenge of List Bouncy Numbers with Power Query
Power Query solution 1 for List Bouncy Numbers, proposed by Aditya Kumar Darak 🇮🇳:
let
MyFun = (Number) =>
let
T = Text.From(Number),
L = Text.ToList(T),
R = List.Sort(L) <> L and List.Sort(L, 1) <> L
in
R,
Generate = List.Generate(
() => [a = 9, c = null, d = 0],
each [d] <= 10000,
each [a = [a] + 1, b = MyFun(a), c = if b then a else null, d = [d] + Number.From(b)],
each [c]
),
Return = List.RemoveNulls(Generate)
in
ReturnPower Query solution 2 for List Bouncy Numbers, proposed by Ramiro Ayala Chávez:
let
a = {10 .. 12000},
b = List.Transform(a, each Text.ToList(Text.From(_))),
c = List.Select(b, each _ <> List.Sort(_, 0) and _ <> List.Sort(_, 1)),
d = List.Transform(c, each Number.From(Text.Combine(_))),
Sol = Table.FirstN(Table.FromColumns({d}, {"Answer Expected"}), 10000)
in
SolSolving the challenge of List Bouncy Numbers with Excel
Excel solution 1 for List Bouncy Numbers, proposed by Bo Rydobon 🇹🇭:
=TAKE(
TOCOL(
MAP(
SEQUENCE(
12000
),
LAMBDA(
x,
LET(
s,
SEQUENCE(
LEN(
x
)-1
),
d,
MID(
x,
s,
1
)-MID(
x,
s+1,
1
),
x/OR(
d>0
)/OR(
d<0
)
)
)
),
3
),
10^4
)Excel solution 2 for List Bouncy Numbers, proposed by John V.:
=TAKE(
TOCOL(
MAP(
ROW(
1:12000
),
LAMBDA(
x,
LET(
i,
MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
a,
DROP(
i,
1
),
b,
DROP(
i,
-1
),
x/OR(
b>a
)/OR(
a>b
)
)
)
),
2
),
10^4
)Excel solution 3 for List Bouncy Numbers, proposed by محمد حلمي:
=TOCOL(
MAP(
SEQUENCE(
11839
),
LAMBDA(
a,
a/LET(
c,
MID(
a,
SEQUENCE(
LEN(
a
)
),
1
),
v,
DROP(
c,
1
),
x,
DROP(
c,
-1
),
OR(
v>x
)*OR(
vExcel solution 4 for List Bouncy Numbers, proposed by Kris Jaganah:
=TAKE(TOCOL(MAP(SEQUENCE(
20000
),
LAMBDA(x,
LET(a,
MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
b,
DROP(
a,
1
)-DROP(
a,
-1
),
c,
SUM(
b,
ABS(
b
)
),
x/(((c=SUM(
b*2
))=(c=0))<>(ROWS(
UNIQUE(
a
)
)=1))))),
3),
10^4)Excel solution 5 for List Bouncy Numbers, proposed by Julian Poeltl:
=TAKE(
LET(
S,
SEQUENCE(
12000,
,
100
),
F,
MAP(
S,
LAMBDA(
A,
SUM(
--DROP(
DROP(
MID(
A,
SEQUENCE(
,
LEN(
A
)
),
1
),
,
1
)>=MID(
A,
SEQUENCE(
,
LEN(
A
)
),
1
),
,
-1
)
)=LEN(
A
)-1
)
),
FF,
MAP(
S,
LAMBDA(
A,
SUM(
--DROP(
DROP(
MID(
A,
SEQUENCE(
,
LEN(
A
)
),
1
),
,
1
)<=MID(
A,
SEQUENCE(
,
LEN(
A
)
),
1
),
,
-1
)
)=LEN(
A
)-1
)
),
FILTER(
S,
MAP(
F,
FF,
LAMBDA(
A,
B,
SUM(
--A,
--B
)
)
)=0
)
),
10000
)Excel solution 6 for List Bouncy Numbers, proposed by Timothée BLIOT:
=LET(S,
SEQUENCE(
10^5,
,
100
),
TAKE(FILTER(S,
NOT(MAP(S,
LAMBDA(x,
LET(A,
LEN(
x
)-1,
B,
SEQUENCE(
A
),
C,
MID(
x,
B,
1
)-MID(
x,
B+1,
1
),
OR(SUM(--(C>=0))=A,
SUM(--(C<=0))=A)))))),
10^4))Excel solution 7 for List Bouncy Numbers, proposed by Sunny Baggu:
=TAKE(
LET(
n,
SEQUENCE(
15000,
,
100
),
FILTER(
n,
MAP(
n,
LAMBDA(
x,
LET(
m,
MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
a,
DROP(
m,
-1
),
b,
DROP(
m,
1
),
c,
a > b,
d,
a < b,
AND(
OR(
c
),
OR(
d
)
)
)
)
)
)
),
10000
)Excel solution 8 for List Bouncy Numbers, proposed by Abdallah Ally:
=LET(
n,
10^4,
b,
SEQUENCE(
2*n,
,
10
),
f,
LAMBDA(
x,
LET(
a,
MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
b,
DROP(
a,
1
),
c,
DROP(
a,
-1
),
SUM(
-AND(
b>=c
),
-AND(
b<=c
)
)=0
)
),
TAKE(
FILTER(
b,
MAP(
b,
LAMBDA(
x,
f(
x
)
)
)
),
n
)
)Excel solution 9 for List Bouncy Numbers, proposed by Sandeep Marwal:
=TAKE(
LET(
range,
SEQUENCE(
100000
),
ans,
HSTACK(
range,
MAP(
range,
LAMBDA(
x,
OR(
ISNUMBER(
REDUCE(
10,
--MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
LAMBDA(
a,
b,
IF(
a="NA",
"NA",
IF(
b<=a,
b,
"NA"
)
)
)
)
),
ISNUMBER(
REDUCE(
0,
--MID(
x,
SEQUENCE(
LEN(
x
)
),
1
),
LAMBDA(
a,
b,
IF(
a="NA",
"NA",
IF(
b>=a,
b,
"NA"
)
)
)
)
)
)
)
)
),
FILTER(
CHOOSECOLS(
ans,
1
),
NOT(
CHOOSECOLS(
ans,
2
)
)
)
),
10000
)Excel solution 10 for List Bouncy Numbers, proposed by Tyler Cameron:
=TOCOL(--MAP(SEQUENCE(
11740,
,
100
),
LAMBDA(p,
LET(t,
MID(
p,
SEQUENCE(
LEN(
p
)
),
1
),
u,
LEFT(
DROP(
REDUCE(
INDEX(
t,
1
),
t,
LAMBDA(
x,
y,
LET(
a,
CONCAT(
x
),
b,
RIGHT(
a,
1
),
VSTACK(
x,
IF(
y=b,
"e"&y,
IF(
y>b,
"g"&y,
"l"&y
)
)
)
)
)
),
1
),
1
),
f,
CONCAT(
FILTER(
u,
u<>"e"
)
),
IF(AND(LEN(
f
)>1,
SUM(--(f<>REPT(
{"l",
"g"},
LEN(
f
)
)))=2),
p,
"")))),
3)Solving the challenge of List Bouncy Numbers with Python
Python solution 1 for List Bouncy Numbers, proposed by Konrad Gryczan, PhD:
import pandas as pd
test = pd.read_excel("466 Bouncy Numbers.xlsx", usecols="A")
def is_bouncy(n):
n = str(n)
increasing = True
decreasing = True
for i in range(len(n) - 1):
if n[i] < n[i + 1]:
decreasing = False
if n[i] > n[i + 1]:
increasing = False
return not increasing and not decreasing
def bouncy_numbers(n):
bo&uncy = []
i = 1
while len(bouncy) < n:
if is_bouncy(i):
bouncy.append(i)
i += 1
return bouncy
result = bouncy_numbers(10000)
print(test['Answer Expected'].tolist() == result) # True
Solving the challenge of List Bouncy Numbers with Python in Excel
Python in Excel solution 1 for List Bouncy Numbers, proposed by Abdallah Ally:
import pandas as pd
import numpy as np
file_path = 'Excel_Challenge_466 - Bouncy Numbers.xlsx'
df = pd.read_excel(file_path)
# Perform data wrangling
def bouncy_numbers(n):
number, numbers = 10, []
while len(numbers) < n:
a = np.array(list(str(number)[1 : ]), int)
b = np.array(list(str(number)[ : -1]), int)
if not all(a >= b) + all(a <= b):
numbers.append(number)
number += 1
return numbers
df['My Answer'] = bouncy_numbers(10000)
df['Check'] = df.iloc[: , 0] == df.iloc[: , 1]
df
Python in Excel solution 2 for List Bouncy Numbers, proposed by Owen Price:
Explainer:
Code for F# and Python solutions:
https://gist.github.com/ncalm/fe6cc6f88dcd2fdfb93451c4601932cc
Solving the challenge of List Bouncy Numbers with R
R solution 1 for List Bouncy Numbers, proposed by Konrad Gryczan, PhD:
library(tidyverse)
library(readxl)
test = read_excel("Excel/466 Bouncy Numbers.xlsx", range = "A1:A10001")
is_bouncy = function(n) {
digits = str_split(as.character(n), "")[[1]] %>% as.integer()
is_decreasing = all(digits == cummin(digits))
is_increasing = all(digits == cummax(digits))
return(!is_decreasing & !is_increasing)
}
find_bouncy_numbers = function(limit) {
bouncy_numbers = integer(limit)
count = 0
num = 100
while (count < limit) {
if (is_bouncy(num)) {
count = count + 1
bouncy_numbers[count] = num
}
num = num + 1
}
bouncy_numbers
}
bouncy_numbers = find_bouncy_numbers(10000)
all.equal(as.numeric(test$`Answer Expected`), bouncy_numbers)
# TRUE
Solving the challenge of List Bouncy Numbers with Excel VBA
Excel VBA solution 1 for List Bouncy Numbers, proposed by Rushikesh K.:
Option Explicit
Sub PrintBouncyNumbers()
Dim ws As Worksheet
Set ws = ThisWorkbook.Sheets("Sheet2")
Dim row As Long
row = 2
Dim num As Long
Dim bC As Long
bC = 0
num = 1
Do While bC < 10000
If IB(num) Then
ws.Cells(row, 1).Value = num
row = row + 1
bC = bC + 1
End If
num = num + 1
Loop
End Sub
Function IB(number As Long) As Boolean
Dim numStr As String
numStr = CStr(number)
Dim inc As Boolean
Dim dec As Boolean
inc = False
dec = False
Dim i As Integer
For i = 1 To Len(numStr) - 1
If Mid(numStr, i, 1) < Mid(numStr, i + 1, 1) Then
inc = True
ElseIf Mid(numStr, i, 1) > Mid(numStr, i + 1, 1) Then
dec = True
End If
If inc And dec Then
IB = True
Exit Function
End If
Next i
IB = False
End Function
&&