fn quick_sort<T: Ord>(arr: &mut [T]) {
if arr.len() <= 1 {
return;
}
let pivot_index = partition(arr);
let (left, right) = arr.split_at_mut(pivot_index);
quick_sort(left);
quick_sort(&mut right[1..]);
}
fn partition<T: Ord>(arr: &mut [T]) -> usize {
let len = arr.len();
let pivot_index = len - 1;
let mut i = 0;
for j in 0..pivot_index {
if arr[j] <= arr[pivot_index] {
arr.swap(i, j);
i += 1;
}
}
arr.swap(i, pivot_index);
i
}