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 Node { |
| 2 | int val; |
| 3 | Node* next; |
| 4 | }; |
| 5 | |
| 6 | Node* build(const vector<int>& values) { |
| 7 | |
| 8 | Node stub{0, nullptr}; |
| 9 | Node* tail = &stub; |
| 10 | |
| 11 | for (int v : values) { |
| 12 | tail->next = new Node{v, nullptr}; |
| 13 | tail = tail->next; |
| 14 | } |
| 15 | |
| 16 | return stub.next; |
| 17 | } |
| 18 | |
| 19 | bool loops(Node* head) { |
| 20 | |
| 21 | Node* slow = head; |
| 22 | Node* fast = head; |
| 23 | |
| 24 | while (fast && fast->next) { |
| 25 | |
| 26 | slow = slow->next; |
| 27 | fast = fast->next->next; |
| 28 | |
| 29 | if (slow == fast) { |
| 30 | return true; |
| 31 | } |
| 32 | } |
| 33 | |
| 34 | return false; |
| 35 | } |
| 36 | |
| 37 | bool solution(const vector<int>& values, int joinAt) { |
| 38 | |
| 39 | Node* head = build(values); |
| 40 | |
| 41 | if (joinAt >= 0 && head) { |
| 42 | |
| 43 | Node* target = head; |
| 44 | |
| 45 | for (int i = 0; i < joinAt; i++) { |
| 46 | target = target->next; |
| 47 | } |
| 48 | |
| 49 | Node* tail = head; |
| 50 | |
| 51 | while (tail->next) { |
| 52 | tail = tail->next; |
| 53 | } |
| 54 | |
| 55 | tail->next = target; |
| 56 | } |
| 57 | |
| 58 | return loops(head); |
| 59 | } |
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.