文章目录

1. 1. Lexicographical Numbers

Lexicographical Numbers

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这道题目用递归来做,”10”<”100”

void helper(int start, int end, vector<int> &v)
{
	if (start <= end)
	{
		v.push_back(start);
		helper(start*10, end, v);
		if (start+1 <= (start / 10) * 10 + 9)
			helper(start+1,end,v);
	}
}

vector<int> lexicalOrder(int n) {
	vector<int> v;

	helper(1, n, v);

	return v;
}