Give it an input and say what you think comes back. It compiles and runs for real, so a wrong guess still shows you the answer — probe as much as you like. Only correct predictions count.
Locked until you have predicted 4 outputs correctly.
| 1 | int solution(const vector<int>& nums) { |
| 2 | if (nums.empty()) return 0; |
| 3 | int left = 0; |
| 4 | int right = nums.size() - 1; |
| 5 | int leftMax = nums[left]; |
| 6 | int rightMax = nums[right]; |
| 7 | int total = 0; |
| 8 | while (left < right) { |
| 9 | if (leftMax < rightMax) { |
| 10 | left++; |
| 11 | if (nums[left] > leftMax) leftMax = nums[left]; |
| 12 | total += leftMax - nums[left]; |
| 13 | } else { |
| 14 | right--; |
| 15 | if (nums[right] > rightMax) rightMax = nums[right]; |
| 16 | total += rightMax - nums[right]; |
| 17 | } |
| 18 | } |
| 19 | return total; |
| 20 | } |
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.