Type an input and write what you think is the output . Each problem is converted to Web Assembly, so any possible input will show the corresponding output. Only correct predictions count.
Locked until you have predicted 3 outputs correctly.
| 1 | struct Store { |
| 2 | |
| 3 | map<string, vector<pair<int, string>>> history; |
| 4 | |
| 5 | void put(const string& key, const string& value, int at) { |
| 6 | history[key].push_back({at, value}); |
| 7 | } |
| 8 | |
| 9 | string get(const string& key, int at) { |
| 10 | |
| 11 | const auto& stamps = history[key]; |
| 12 | |
| 13 | int lo = 0; |
| 14 | int hi = (int)stamps.size() - 1; |
| 15 | string found; |
| 16 | |
| 17 | while (lo <= hi) { |
| 18 | |
| 19 | int mid = lo + (hi - lo) / 2; |
| 20 | |
| 21 | if (stamps[mid].first <= at) { |
| 22 | found = stamps[mid].second; |
| 23 | lo = mid + 1; |
| 24 | } else { |
| 25 | hi = mid - 1; |
| 26 | } |
| 27 | } |
| 28 | |
| 29 | return found; |
| 30 | } |
| 31 | }; |
| 32 | |
| 33 | vector<string> solution(const vector<string>& ops, |
| 34 | const vector<string>& keys, |
| 35 | const vector<string>& values, |
| 36 | const vector<int>& times) { |
| 37 | |
| 38 | Store store; |
| 39 | vector<string> ans; |
| 40 | |
| 41 | int n = ops.size(); |
| 42 | |
| 43 | for (int i = 0; i < n; i++) { |
| 44 | |
| 45 | if (ops[i] == "set") { |
| 46 | store.put(keys[i], values[i], times[i]); |
| 47 | ans.push_back("null"); |
| 48 | |
| 49 | } else { |
| 50 | ans.push_back(store.get(keys[i], times[i])); |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | return ans; |
| 55 | } |
Names have been stripped. The signature is the only clue you get for free. Compiled as C++20 with the standard headers and using namespace std; already in scope.