CF297A.Parity Game

You are fishing with polar bears Alice and Bob. While waiting for the fish to bite, the polar bears get bored. They come up with a game. First Alice and Bob each writes a 01-string (strings that only contain character "0" and "1") a and b. Then you try to turn a into b using two types of operations:

• Write parity(a) to the end of a. For example, .
• Remove the first character of a. For example, . You cannot perform this operation if a is empty.

You can use as many operations as you want. The problem is, is it possible to turn a into b?

The parity of a 01-string is 1 if there is an odd number of "1"s in the string, and 0 otherwise.

你正在与北极熊爱丽丝（Alice）和鲍勃（Bob）一起钓鱼。在等待鱼儿上钩时，这两只北极熊感到无聊，于是想出了一个游戏：首先，爱丽丝和鲍勃各自写下一个 01 字符串（即仅由字符 "0" 和 "1" 构成的字符串）$a$ 和 $b$；接着，你尝试通过以下两种操作将 $a$ 变为 $b$：

• 将 $a$ 的奇偶性（parity）添加到 $a$ 的末尾。例如，。
• 删除 $a$ 的第一个字符。例如，。若 $a$ 为空，则不能执行此操作。

你可以任意多次使用上述操作。问题是：能否将 $a$ 变为 $b$？

一个 01 字符串的奇偶性定义为：若该字符串中 "1" 的个数为奇数，则奇偶性为 $1$；否则为 $0$。

The first line contains the string a and the second line contains the string b (1 ≤ |a|, |b| ≤ 1000). Both strings contain only the characters "0" and "1". Here |x| denotes the length of the string x.

第一行包含字符串 $a$，第二行包含字符串 $b$（$1 ≤ |a|, |b| ≤ 1000$）。两个字符串仅由字符 "0" 和 "1" 组成。其中 $|x|$ 表示字符串 $x$ 的长度。

Print "YES" (without quotes) if it is possible to turn a into b, and "NO" (without quotes) otherwise.

如果可以将 a 变为 b，则输出 "YES"（不带引号）；否则输出 "NO"（不带引号）。

In the first sample, the steps are as follows: 01011 → 1011 → 011 → 0110

在第一个样例中，步骤如下：01011 → 1011 → 011 → 0110