Peter
Peter Campbell Smith

The weekly challenge

My solutions

My solutions

 Date Week Task 1 Task 2
 08.07.24  277

Count common

Strong pair

 01.07.24  276

Complete day

Maximum frequency

 24.06.24  275

Broken keys

Replace digits

 17.06.24  274

Goat Latin

Bus route

 10.06.24  273

Percentage of character

B after A

 03.06.24  272

Defang IP address

String score

 27.05.24  271

Maximum ones

Sort by 1 bits

 20.05.24  270

Special positions

Equalize array

 13.05.24  269

Bitwise or

Distribute elements

 06.05.24  268

Magic numbers

Number game

 29.04.24  267

Product sign

Line counts

 22.04.24  266

Uncommon words

X matrix

 15.04.24  265

33% appearance

Completing word

 08.04.24  264

Greatest English letter

Target array

 01.04.24  263

Target index

Merge items

 25.03.24  262

Max positive negative

Count equal divisible

 18.03.24  261

Element digit sum

Multiply by 2

 11.03.24  260

Unique occurrences

Dictionary rank

 04.03.24  259

Banking day offset

Line parser

 26.02.24  258

Count even digits number

Sum of values

 19.02.24  257

Smaller than current

Reduced row echelon

 12.02.24  256

Maximum pairs

Merge strings

 05.02.24  255

Odd character

Most frequent word

 29.01.24  254

Three power

Reverse vowels

 22.01.24  253

Split strings

Weakest row

 15.01.24  252

Special numbers

Unique sum zero

 08.01.24  251

Concatenation Value

Lucky numbers

 01.01.24  250

Smallest index

Alphanumeric string value

 25.12.23  249

Equal pairs

DI string match

 18.12.23  248

Shortest distance

Submatrix sum

 11.12.23  247

Secret Santa

Most frequent letter pair

 04.12.23  246

6 out of 49

Sort language

 27.11.23  245

Sort language

Largest of three

 20.11.23  244

Count smaller

Group hero

 13.11.23  243

Reverse pairs

Floor sum

 06.11.23  242

Missing members

Flip matrix

 30.10.23  241

Arithmetic triplets

Prime order

 23.10.23  240

Acronym

Build array

 16.10.23  239

Same string

Consistent strings

 09.10.23  238

Running sum

Persistence sort

 09.10.23  237

Seize the day

Maximise greatness

 25.09.23  236

Exact change

Array loops

 18.09.23  235

Remove one

Duplicate zeroes

 11.09.23  234

Common characters

Unequal triplets

 04.09.23  233

Similar words

Frequency sort

 21.08.23  231

Min max

Senior citizens

 14.08.23  230

Separate digits

Count words

 07.08.23  229

Lexicographically ordered

Two out of three

 31.07.23  228

Unique sum

Empty array

 24.07.23  227

Friday 13th

Roman maths

 17.07.23  226

Shuffle strings

Zero array

 10.07.23  225

Max words

Left right sum diff

 03.07.23  224

Special notes

Additive number

 26.06.23  223

Count primes

Box coins

 19.06.23  222

Matching members

Last member

 12.06.23  221

Good strings

Arithmetic subsequences

 05.06.23  220

Common characters

Squareful

 29.05.23  219

Sorted squares

Travel expenditure

 22.05.23  218

Maximum product

Matrix sum

 15.05.23  217

Sorted matrix

Max number

 08.05.23  216

Registration number

Word stickers

 01.05.23  215

Odd one out

Number placement

 24.04.23  214

Rank score

Collect points

 17.04.23  213

Fun sort

Shortest route

 10.04.23  212

Jumping letters

Sequential substrings

 03.04.23  211

Toeplitz matrix

Split same average

 27.03.23  210

Kill and win

Number collision

 20.03.23  209

A 3-letter alphabet

Merging emails

 13.03.23  208

Minimum index sum

Duplicate and missing

 06.03.23  207

Linear words

The H-index for citations

 27.02.23  206

Measuring the gaps

Array pairings

 20.02.23  205

Third highest value

Maximum xor

 13.02.23  204

Uphill or downhill?

Reshape matrix

 06.02.23  203

Special quads

Copy folders

 30.01.23  202

Three odd things

Find the valleys

 23.01.23  201

Missing numbers

Piles of pennies

 16.01.23  200

Arithmetic slices

Seven segment 200

 09.01.23  199

Good pairs

Good triplets

 02.01.23  198

Max gap

Prime count

 19.12.22  196

Pattern 132

Range list

 12.12.22  195

Special integers

Most frequent even

 07.12.22  194

Digital clock

Frequency equalizer

 28.11.22  193

Binary string

Odd string

 21.11.22  192

Binary flip

Equal Distribution

 14.11.22  191

Twice largest

Cute List

 07.11.22  190

Capital detection

Decoded List

 31.10.22  189

Greater character

Array degree

 24.10.22  188

Divisible Pairs

Total Zero

 17.10.22  187

Days together

Magical triplets

 10.10.22  186

Zip list

Unicode makeover

 03.10.22  185

Mac address

Mask code

 26.09.22  184

Sequence number

Split array

 19.09.22  183

Unique array

Date difference

 12.09.22  182

Max index

Common path

 05.09.22  181

Sentence order

Hot day

 15.08.22  178

Quater-imaginary base

Business date

 08.08.22  177

Damm algorithm

Palindromic prime cyclops

 01.08.22  176

Permuted multiples

Reversible numbers

 25.07.22  175

Last Sunday

Perfect totient numbers

 18.07.22  174

Disarium numbers

Permutation ranking

 11.07.22  173

Esthetic number

Sylvester’s sequence

 04.07.22  172

Prime partition

Five-number summary

 27.06.22  171

Abundant number

 20.06.22  170

Primorial numbers

Kronecker product

 13.06.22  169

Brilliant numbers

Achilles numbers

 06.06.22  168

Perrin prime

Home prime

 30.05.22  167

Circular prime

Gamma function

 23.05.22  166

Hexadecimal words

K-directory diff

 16.05.22  165

Scalable vector graphics

Line of best fit

 09.05.22  164

Prime palindrome

Happy numbers

 02.05.22  163

Sum bitwise operator

Summations

 25.04.22  162

ISBN-13

Wheatstone-Playfair

 18.04.22  161

Abecedarian words

Pangrams

 11.04.22  160

Four is magic

Equilibrium index

 28.03.22  158

Additive primes

First series Cuban primes

 21.03.22  157

Pythagorean means

Brazilian number

 14.03.22  156

Pernicious numbers

Weird number

 07.03.22  155

Fortunate numbers

Pisano period

 28.02.22  154

Missing permutation

Padovan primes

 21.02.22  153

Left factorials

Factorions

 14.02.22  152

Triangle sum path

Rectangle area

 07.02.22  151

Binary tree depth

Rob the house

 31.01.22  150

Fibonacci words

Square-free integer

 24.01.22  149

Fibonacci digit sum

Largest square

 17.01.22  148

Eban numbers

Cardano triplets

 10.01.22  147

Truncatable prime

Pentagon numbers

 03.01.22  146

10001st prime number

Curious fraction tree

 27.12.21  145

Dot product

Palindromic tree

 20.12.21  144

Semiprime

Ulam sequence

 13.12.21  143

Calculator

Stealthy number

 06.12.21  142

Divisor last digit

Sleep sort

 29.11.21  141

Number divisors

Like numbers

 22.11.21  140

Add binary

Multiplication table

 15.11.21  139

JortSort

Long primes

 08.11.21  138

Workdays

Split number

 18.10.21  135

Middle 3-digits

Validate SEDOL

 11.10.21  134

Pandigital numbers

Distinct terms count

 04.10.21  133

Integer square root

Smith numbers

 20.09.21  131

Consecutive arrays

Find pairs

 13.09.21  130

Odd number

Binary search tree

 06.09.21  129

Add linked lists

 30.08.21  128

Minimum platforms

 09.08.21  125

Pythagorean triples

 02.08.21  124

Tug of war

• Occasionally older 'try it' buttons don't work, because of later changes to the way this website works. If you let me know (email link) I will (try to) fix them.

• If a task is missing above, I didn't submit a solution to the challenge.

The content of this website which has been created by
Peter Campbell Smith is hereby placed in the public domain