| 1 | // counting_sort.rs |
| 2 | |
| 3 | fn counting_sort(nums: &mut [usize]) { |
| 4 | if nums.len() < 2 { return; } |
| 5 | |
| 6 | // 桶数量为 nums 中最大值加 1，保证数据都有桶放 |
| 7 | let max_bkt_num = 1 + nums.iter().max().unwrap(); |
| 8 | let mut counter = vec![0; max_bkt_num]; |
| 9 | |
| 10 | // 将数据标记到桶 |
| 11 | for &v in nums.iter() { |
| 12 | counter[v] += 1; |
| 13 | } |
| 14 | |
| 15 | // 数据写回原 nums 切片 |
| 16 | // j 表示 nums 的下标 |
| 17 | let mut j = 0; |
| 18 | for i in 0..max_bkt_num { |
| 19 | while counter[i] > 0 { |
| 20 | nums[j] = i; |
| 21 | counter[i] -= 1; |
| 22 | j += 1; |
| 23 | } |
| 24 | } |
| 25 | } |
| 26 | |
| 27 | fn main() { |
| 28 | let mut nums = [54,32,99,18,75,31,43,56,21,22]; |