Counting in binary
"a" represents 0; "A" represents 1. Start from zero and count to 15.
Start file
aaaa
End file
aaaa aaaA aaAa aaAA aAaa aAaA aAAa aAAA Aaaa AaaA AaAa AaAA AAaa AAaA AAAa AAAA
View Diff
1a2,16 > aaaA > aaAa > aaAA > aAaa > aAaA > aAAa > aAAA > Aaaa > AaaA > AaAa > AaAA > AAaa > AAaA > AAAa > AAAA
Solutions by @thomasguillory:
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