#include #include // std::distance #include #include #include /* Idea from: https://www.sololearn.com/Discuss/2187885/?ref=app Hello, can someone help me to rank numbers. Example: Input: a = [35, 26, 65, 15] Output: [2nd, 3rd, 1st, 4th] */ std::string rank(auto n) { const char* ranks[4] = { "th", "st", "nd", "rd" }; std::size_t i = n % 10; if(i && i < 4) { if(n < 11 || n > 13) return std::to_string(n).append(ranks[i]); } return std::to_string(n).append(ranks[0]); } int main() { std::vector vi; int v; while(std::cin >> v) { // Check for duplicate number input std::vector::iterator pos {std::find(vi.begin(), vi.end(), v)}; if(pos != vi.end()) continue; vi.push_back(v); } std::cout << "Source:\n"; if(!vi.size()) { std::cout << "(Empty)\n"; return 0; } for(int e : vi) std::cout << e << " "; std::cout << "\n\nSorted:\n"; std::vector svi {vi}; std::sort(svi.begin(), svi.end(), std::greater()); for(int e : svi) std::cout << e << " "; std::cout << "\n\nRank:\n"; for(int needle : vi) { // std::vector::iterator it {std::lower_bound(svi.begin(), svi.end(), needle)}; // PROBLEM: // std::lower_bound DOESN'T WORK when vector is sorted in descending order. // UPDATE: // std::lower_bound WORKS by using reverse_iterator instead of normal_iterator, which swaps the range begin and range end - effectively. // Suggested by @~swim~ std::vector::reverse_iterator it {std::lower_bound(svi.rbegin(), svi.rend(), needle)}; if(it != svi.rend() && *it == needle) { std::cout << needle << " rank " << rank(std::distance(it, svi.rend())) << "\n"; } } return 0; }

Rank of numbers in vector