# HackerRank ‘Strange Counter’ Solution

##### Short Problem Definition:

Bob has a *strange counter*. At the first second, it displays the number *3*. Each second, the number displayed by the counter decrements by *1* until it reaches *1*.

The counter counts down in cycles. In next second, the timer resets to *2x the initial number for the prior cycle* and continues counting down.

##### Link

##### Complexity:

time complexity is O(log(N))

space complexity is O(1)

##### Execution:

This is a ‘simple’ mathematical problem that requires no while loops. First, find out what cycle the value T belongs to. Secondly, determine the value at the end of the cycle. Go back T steps to figure out the exact value at T.

Be careful, this can easily int overflow in C++, if the input is large enough.

##### Solution:

#include <bits/stdc++.h> using namespace std; // Complete the strangeCounter function below. long strangeCounter(long t) { return 6 * pow(2, floor(log2((t+2)/3))) - 2 - t; } int main() { ofstream fout(getenv("OUTPUT_PATH")); long t; cin >> t; cin.ignore(numeric_limits<streamsize>::max(), '\n'); long result = strangeCounter(t); fout << result << "\n"; fout.close(); return 0; }

If you enjoyed this post, then make sure you subscribe to my Newsletter and/or Feed.