Polo the Penguin and the Lucky String

CodeChefRating 2461Open on judge ↗

Read problems statements in Russian here Polo, the Penguin, likes lucky strings - the strings that consist only of lucky digits 4 and 7. He has a lucky string S. Digits in this string are numbered from left to right starting with 1. He performs the following operations on the string while it is possible to do so: - Find a set of all positions, P, such that for every position i in P, S[i] = 4 an

HINT LADDERno hints yet

L1 Observation

L2 Technique

L3 Approach

L4 Pseudo-code

🔒

L5 Full solution

L5 unlocks only if you insist twice

solution.cppC++17

CodeSearch Tutor

Hints, not spoilers — it won’t hand over the full solution unless you insist.

voice by Sarvam AI