求最长非升子序列长度

求最长非升子序列长度，主要使用dfs（递归实现）以及dp两种方法。源码如下：

#include <iostream>
using namespace std;

//overrall variable
int * numbers;
int * dp;
int nums;
int max_length_dfs;
int max_length_dp;


//dfs-recursively implemented
void dfs_recursive(int * number,int pos,int length)
{
	for(int i = pos;i < nums;i++)
	{
		if(number[i] < number[pos])
		{
			dfs_recursive(number,i,length+1);
		}
	}
	if(length > max_length_dfs)
	{
		max_length_dfs = length;
	}

}
int dping(int pos)
{
	if(dp[pos] > 0)
		return dp[pos];
	int max = 0;
	for(int i = 0;i < pos;i++)
	{
		if(dping(i) > max && numbers[i] >= numbers[pos])
			max = dping(i);
	}
	dp[pos] = max + 1;
	return dp[pos];

}


int main()
{
	cin >> nums;
	numbers = new int[nums];
	dp = new int[nums];
	for(int i = 0;i < nums;i++)
	{
		cin >> numbers[i];
		dp[i] = 0;
	}
	//dfs
	dfs_recursive(numbers,0,1);

	//dp
	for(int i = 0;i < nums;i++)
	{
		if(dping(i) > max_length_dp)
			max_length_dp = dping(i);
	}
	
	cout << "The result by dfs: " << max_length_dfs << endl;
	cout << "The result by dp: " << max_length_dp << endl;
	//free
	delete [] numbers;
	delete [] dp;
	system("pause");
}