/* [Challenge] Guess the sequence! I have a sequence of numbers in mind. I'll call it A. It contains all numbers 1 through n exactly once and nothing else, for some positive integer n. They need not be in order. But to make it more interesting for you to guess my sequence, I give you another sequence B instead. Such that for every 1 <= i <= n, B[i] (starting index from 1) is the number of elements of the original sequence A, that come before i in the sequence (smaller index) and are greater than i. Your mission, should you choose to accept it, is to reconstruct A given B. See the comment below for examples. https://www.sololearn.com/post/208710/?ref=app */ #include #include #include #include using namespace std; // n is number of newlines to insert auto Print = [](auto&& to_print, int n=1) { cout << "["; for(auto it=begin(to_print); it!=prev(end(to_print)); ++it){ cout << *it << ", "; } cout << *prev(end(to_print)); cout << "]"; cout << string(n,'\n'); }; // Main algo auto reconstruct = [](auto&& sample){ list out; for(size_t i=sample.size(); i>0; --i) out.insert(next(begin(out), sample.at(i-1)),i); return out; }; int main() { // sample inputs vector> inp{ {3,0,1,2,1,0}, {0,0,0,0}, {1,4,2,0,1,0}, {0,7,3,0,2,3,1,1,0}, {13,12,1,0,11,1,1,5,10,1,7,6,4,5,0,0,1,0,0}, {21,20,16,11,4,15,1,14,12,1,6,8,6,6,6,6,1, 2,0,2,1,0}, {8,7,24,7,19,6,11,8,5,4,4,3,13,6,3,8,7,6,3, 2,2,1,3,2,2,0,0}, {5,6,26,6,9,2,19,5,6,13,1,11,4,5,13,6,11, 8,10,5,4,7,5,2,5,5,0,0,1,1,0}, {6,2,27,23,17,13,9,8,7,17,8,5,4,14,16,11,8, 1,11,3,1,1,4,10,5,8,7,1,2,4,2,0,1,0}}; for(auto&& sample : inp){ cout << "B: ";Print(sample); cout << "A: ";Print(reconstruct(sample),3); } }

[Challenge] Guess_the_sequence.cpp