重复元素全排列-分治法

#include <iostream>
#include <cmath>
using namespace std;

int total = 0;
template <typename T>
bool  check(T nums[], int low, int hight) 
{//查询是否与前面重复
	for (int i = low; i < hight; i++) 
	{
		if (nums[i] == nums[hight])
		{
			return false;
		}
	}
	return true;
}

//数组元素交换
template <typename T>
void swap(T nums[],int low,int hight)
{
	T temp = nums[low];
	nums[low] = nums[hight];
	nums[hight] = temp;
}

template <typename T>
void perm(T nums[], int low, int hight)
{
	if (low == hight) {	//
		total++;//
		cout << ' ' << total << "   :";
		for (int i = 0; i < hight; i++) {
			cout << nums[i] << ' ';
		}
		cout << endl;
	}
	else {
		for (int i = low; i < hight; i++)
		{
			if (check(nums, low, i))//没有重复元素
			{
				swap(nums, low, i);//
				perm(nums, low + 1, hight);
				swap(nums, low, i);//到最后两个元素开始调用该方法

			}
		}
	}
}


int main() {
	int nums[] = { 1,1,2,3 };
	perm<int>(nums, 0, 4);
	return 0;
}