Recursive helper function to sort numbers in ascending sequence Numbers to be sorted are from words[start] to words[end]
| 94 | // Recursive helper function to sort numbers in ascending sequence |
| 95 | // Numbers to be sorted are from words[start] to words[end] |
| 96 | void sort(std::vector<unsigned>& numbers, size_t start, size_t end) |
| 97 | { |
| 98 | // start index must be less than end index for 2 or more elements |
| 99 | if (!(start < end)) |
| 100 | return; |
| 101 | |
| 102 | // Choose middle of the [start, end] range to partition |
| 103 | swap(numbers, start, (start + end) / 2); // Swap middle number with start |
| 104 | |
| 105 | // Check values against chosen word |
| 106 | size_t current{ start }; |
| 107 | for (size_t i{ start + 1 }; i <= end; i++) |
| 108 | { |
| 109 | if (numbers[i] < numbers[start]) // Is word less than chosen value? |
| 110 | swap(numbers, ++current, i); // Yes, so swap to the left |
| 111 | } |
| 112 | |
| 113 | swap(numbers, start, current); // Swap the chosen value with the last swapped number |
| 114 | |
| 115 | if (current > start) sort(numbers, start, current - 1); // Sort left subset if exists |
| 116 | if (end > current + 1) sort(numbers, current + 1, end); // Sort right subset if exists |
| 117 | } |
| 118 | |
| 119 | // Sort numbers in ascending sequence |
| 120 | void sort(std::vector<unsigned>& numbers) |