zip-bomb

Your mission

Unpack an archive layer by layer, stopping before the size goes over budget.

today's brief

Around 2001 somebody posts a 42 kilobyte file called 42.zip. Unpack it and you get 16 archives, unpack those and each gives you 16 more, five layers down, until 4.5 petabytes of zeroes are landing where your disk used to be. It was built to show what a scanner does when it opens whatever it is handed. Nothing crashed that day. The answer has always been to count the bytes on the way down and stop.

See it in action

layers(42, {10,10,10,10,10}, 5, 1000000)

Expected result

Your checklist

For your own tracking. Tests grade your code.

size is the size before anything is unpacked. ratio holds n layers, applied in order.
Unpacking layer i multiplies the current size by ratio[i].
A layer is unpacked only when the size afterwards is at most limit, and unpacking stops at the first layer that would go over.
Return how many layers were unpacked.

More examples

layers(5, {2}, 1, 10)

Expected result

layers(5, {2}, 1, 9)

Expected result

Constraints

Expected files

unpack.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions

zip-bomb

Your mission

Unpack an archive layer by layer, stopping before the size goes over budget.

today's brief

See it in action

layers(42, {10,10,10,10,10}, 5, 1000000)

Expected result

Your checklist

For your own tracking. Tests grade your code.

size is the size before anything is unpacked. ratio holds n layers, applied in order.
Unpacking layer i multiplies the current size by ratio[i].
A layer is unpacked only when the size afterwards is at most limit, and unpacking stops at the first layer that would go over.
Return how many layers were unpacked.

More examples

layers(5, {2}, 1, 10)

Expected result

layers(5, {2}, 1, 9)

Expected result

Constraints

Expected files

unpack.c

Allowed functions

None. Write every helper yourself.

Back to compete

Solutions