The Weekly Challenge

Peter Campbell Smith

The Weekly Challenge
Week 286

More information

Task 1

Task 2

Perl

Perl home page – all about the language
Perldoc – detailed Perl documentation
CPAN – library of useful Perl modules

Peter's solutions

Date	Task 1	Task 2	Week
09.09.24	Self spammer	Order game	286
02.09.24	No connection	Making change	285
26.08.24	Lucky integer	Relative sort	284
19.08.24	Unique number	Digit count value	283
12.08.24	Good integer	Changing keys	282
05.08.24	Check color	Knight’s move	281
29.07.24	Twice appearance	Count asterisks	280
22.07.24	Sort letters	Split string	279
15.07.24	Sort string	Reverse word	278
08.07.24	Count common	Strong pair	277
01.07.24	Complete day	Maximum frequency	276
24.06.24	Broken keys	Replace digits	275
17.06.24	Goat Latin	Bus route	274
10.06.24	Percentage of character	B after A	273
03.06.24	Defang IP address	String score	272
27.05.24	Maximum ones	Sort by 1 bits	271
20.05.24	Special positions	Equalize array	270
13.05.24	Bitwise or	Distribute elements	269
06.05.24	Magic numbers	Number game	268
29.04.24	Product sign	Line counts	267
22.04.24	Uncommon words	X matrix	266
15.04.24	33% appearance	Completing word	265
08.04.24	Greatest English letter	Target array	264
01.04.24	Target index	Merge items	263
25.03.24	Max positive negative	Count equal divisible	262
18.03.24	Element digit sum	Multiply by 2	261
11.03.24	Unique occurrences	Dictionary rank	260
04.03.24	Banking day offset	Line parser	259
26.02.24	Count even digits number	Sum of values	258
19.02.24	Smaller than current	Reduced row echelon	257
12.02.24	Maximum pairs	Merge strings	256
05.02.24	Odd character	Most frequent word	255
29.01.24	Three power	Reverse vowels	254
22.01.24	Split strings	Weakest row	253
15.01.24	Special numbers	Unique sum zero	252
08.01.24	Concatenation Value	Lucky numbers	251
01.01.24	Smallest index	Alphanumeric string value	250
25.12.23	Equal pairs	DI string match	249
18.12.23	Shortest distance	Submatrix sum	248
11.12.23	Secret Santa	Most frequent letter pair	247
04.12.23	6 out of 49	Sort language	246
27.11.23	Sort language	Largest of three	245
20.11.23	Count smaller	Group hero	244
13.11.23	Reverse pairs	Floor sum	243
06.11.23	Missing members	Flip matrix	242
30.10.23	Arithmetic triplets	Prime order	241
23.10.23	Acronym	Build array	240
16.10.23	Same string	Consistent strings	239
09.10.23	Running sum	Persistence sort	238
09.10.23	Seize the day	Maximise greatness	237
25.09.23	Exact change	Array loops	236
18.09.23	Remove one	Duplicate zeroes	235
11.09.23	Common characters	Unequal triplets	234
04.09.23	Similar words	Frequency sort	233
28.08.23	No challenge was set for this week		232
21.08.23	Min max	Senior citizens	231
14.08.23	Separate digits *	Count words *	230
07.08.23	Lexicographically ordered	Two out of three	229
31.07.23	Unique sum	Empty array	228
24.07.23	Friday 13th	Roman maths	227
17.07.23	Shuffle strings	Zero array	226
10.07.23	Max words	Left right sum diff	225
03.07.23	Special notes	Additive number	224
26.06.23	Count primes	Box coins	223
19.06.23	Matching members	Last member	222
12.06.23	Good strings	Arithmetic subsequences	221
05.06.23	Common characters	Squareful	220
29.05.23	Sorted squares	Travel expenditure	219
22.05.23	Maximum product	Matrix sum	218
15.05.23	Sorted matrix	Max number	217
08.05.23	Registration number	Word stickers	216
01.05.23	Odd one out	Number placement	215
24.04.23	Rank score	Collect points	214
17.04.23	Fun sort	Shortest route	213
10.04.23	Jumping letters	Sequential substrings	212
03.04.23	Toeplitz matrix	Split same average	211
27.03.23	Kill and win	Number collision	210
20.03.23	A 3-letter alphabet	Merging emails	209
13.03.23	Minimum index sum	Duplicate and missing	208
06.03.23	Linear words	The H-index for citations	207
27.02.23	Measuring the gaps	Array pairings	206
20.02.23	Third highest value	Maximum xor	205
13.02.23	Uphill or downhill?	Reshape matrix	204
06.02.23	Special quads	Copy folders	203
30.01.23	Three odd things	Find the valleys	202
23.01.23	Missing numbers	Piles of pennies	201
16.01.23	Arithmetic slices	Seven segment 200	200
09.01.23	Good pairs	Good triplets	199
02.01.23	Max gap	Prime count	198
19.12.22	Pattern 132	Range list	196
12.12.22	Special integers	Most frequent even	195
07.12.22	Digital clock	Frequency equalizer	194
28.11.22	Binary string	Odd string	193
21.11.22	Binary flip	Equal Distribution	192
14.11.22	Twice largest	Cute List	191
07.11.22	Capital detection	Decoded List	190
31.10.22	Greater character	Array degree	189
24.10.22	Divisible Pairs	Total Zero	188
17.10.22	Days together	Magical triplets	187
10.10.22	Zip list	Unicode makeover	186
03.10.22	Mac address	Mask code	185
26.09.22	Sequence number	Split array	184
19.09.22	Unique array	Date difference	183
12.09.22	Max index	Common path	182
05.09.22	Sentence order	Hot day	181
15.08.22	Quater-imaginary base	Business date	178
08.08.22	Damm algorithm	Palindromic prime cyclops	177
01.08.22	Permuted multiples	Reversible numbers	176
25.07.22	Last Sunday	Perfect totient numbers	175
18.07.22	Disarium numbers	Permutation ranking	174
11.07.22	Esthetic number	Sylvester’s sequence	173
04.07.22	Prime partition	Five-number summary	172
27.06.22	Abundant number	First-class function *	171
20.06.22	Primorial numbers	Kronecker product	170
13.06.22	Brilliant numbers	Achilles numbers	169
06.06.22	Perrin prime	Home prime	168
30.05.22	Circular prime	Gamma function	167
23.05.22	Hexadecimal words	K-directory diff	166
16.05.22	Scalable vector graphics	Line of best fit	165
09.05.22	Prime palindrome	Happy numbers	164
02.05.22	Sum bitwise operator	Summations	163
25.04.22	ISBN-13	Wheatstone-Playfair	162
18.04.22	Abecedarian words	Pangrams	161
11.04.22	Four is magic	Equilibrium index	160
04.04.22	Farey sequence *	Möbius number *	159
28.03.22	Additive primes	First series Cuban primes	158
21.03.22	Pythagorean means	Brazilian number	157
14.03.22	Pernicious numbers	Weird number	156
07.03.22	Fortunate numbers	Pisano period	155
28.02.22	Missing permutation	Padovan primes	154
21.02.22	Left factorials	Factorions	153
14.02.22	Triangle sum path	Rectangle area	152
07.02.22	Binary tree depth	Rob the house	151
31.01.22	Fibonacci words	Square-free integer	150
24.01.22	Fibonacci digit sum	Largest square	149
17.01.22	Eban numbers	Cardano triplets	148
10.01.22	Truncatable prime	Pentagon numbers	147
03.01.22	10001st prime number	Curious fraction tree	146
27.12.21	Dot product	Palindromic tree	145
20.12.21	Semiprime	Ulam sequence	144
13.12.21	Calculator	Stealthy number	143
06.12.21	Divisor last digit	Sleep sort	142
29.11.21	Number divisors	Like numbers	141
22.11.21	Add binary	Multiplication table	140
15.11.21	JortSort	Long primes	139
08.11.21	Workdays	Split number	138
01.11.21	Long year *	Lychrel number *	137
25.10.21	Two friendly *	Fibonacci sequence *	136
18.10.21	Middle 3-digits	Validate SEDOL	135
11.10.21	Pandigital numbers	Distinct terms count	134
04.10.21	Integer square root	Smith numbers	133
27.09.21	Mirror dates *	Hash join *	132
20.09.21	Consecutive arrays	Find pairs	131
13.09.21	Odd number	Binary search tree	130
06.09.21	Root distance *	Add linked lists	129
30.08.21	Maximum sub-matrix *	Minimum platforms	128
23.08.21	Disjoint sets *	Conflict intervals *	127
16.08.21	Count numbers *	Minesweeper game *	126
09.08.21	Pythagorean triples	Binary tree diameter *	125
02.08.21	Happy women’s day *	Tug of war	124

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* I did not submit this solution at the time but have since solved it.

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