use std::cmp::PartialOrd;
pub fn partition<T: PartialOrd>(arr: &mut [T], lo: isize, hi: isize) -> isize {
let pivot = hi as usize;
let mut i = lo - 1;
let mut j = hi;
loop {
i += 1;
while arr[i as usize] < arr[pivot] {
i += 1;
}
j -= 1;
while j >= 0 && arr[j as usize] > arr[pivot] {
j -= 1;
}
if i >= j {
break;
} else {
arr.swap(i as usize, j as usize);
}
}
arr.swap(i as usize, pivot as usize);
i
}
fn _quick_sort<T: Ord>(arr: &mut [T], lo: isize, hi: isize) {
if lo < hi {
let p = partition(arr, lo, hi);
_quick_sort(arr, lo, p - 1);
_quick_sort(arr, p + 1, hi);
}
}
pub fn quick_sort<T: Ord>(arr: &mut [T]) {
let len = arr.len();
_quick_sort(arr, 0, (len - 1) as isize);
}