quicksort in c++

quicksort.cpp

#include <vector>

auto partition(std::vector<int>& arr, int start, int end) -> int {
	auto pivotIndex = end;
	for (int i = start; i < pivotIndex; i++) {
		if (arr[i] > arr[pivotIndex]) {
			auto temp = arr[i];
			arr[i] = arr[pivotIndex];
			arr[pivotIndex] = temp;
			pivotIndex = i;
		}
	}
	return pivotIndex;
}

auto quicksort(std::vector<int>& arr, int start, int end) {
	if (start >= end) return;
	auto pivot = partition(arr, start, end);
	quicksort(arr, start, pivot - 1);
	quicksort(arr, pivot + 1, end);
}