d432: 第四題：通關密語 (pwd)

解題心得

跟上一題差不多。

程式碼

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

map<char, int> m;
string inOrder, postOrder;

void printPreorder(int start, int end)
{
	if (start > end) return;

	int val = -1, flag = -1;
	for (int i = start; i <= end; i++)
	{
		if (m[inOrder[i]] > val)
		{
			val = m[inOrder[i]];
			flag = i;
		}
	}
	cout << inOrder[flag];

	printPreorder(start, flag - 1);
	printPreorder(flag + 1, end);
}

int main()
{
	cin >> inOrder >> postOrder;
	for (int i = 0; i < postOrder.length(); i++)
		m[postOrder[i]] = i;
	printPreorder(0, postOrder.length() - 1);
	return 0;
}