CF878A.Short Program

普及/提高-

通过率：0%

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题目描述

Petya learned a new programming language CALPAS. A program in this language always takes one non-negative integer and returns one non-negative integer as well.

In the language, there are only three commands: apply a bitwise operation AND, OR or XOR with a given constant to the current integer. A program can contain an arbitrary sequence of these operations with arbitrary constants from $0$ to $1023$ . When the program is run, all operations are applied (in the given order) to the argument and in the end the result integer is returned.

Petya wrote a program in this language, but it turned out to be too long. Write a program in CALPAS that does the same thing as the Petya's program, and consists of no more than $5$ lines. Your program should return the same integer as Petya's program for all arguments from $0$ to $1023$ .

输入格式

The first line contains an integer $n$ ( $1<=n<=5·10^{5}$ ) — the number of lines.

Next $n$ lines contain commands. A command consists of a character that represents the operation ("&", "|" or "^" for AND, OR or XOR respectively), and the constant $x_{i}$ $0<=x_{i}<=1023$ .

输出格式

Output an integer $k$ ( $0<=k<=5$ ) — the length of your program.

Next $k$ lines must contain commands in the same format as in the input.

输入输出样例

输入#1
```
3
| 3
^ 2
| 1
```
输出#1
```
2
| 3
^ 2
```
输入#2
```
3
& 1
& 3
& 5
```
输出#2
```
1
& 1
```
输入#3
```
3
^ 1
^ 2
^ 3
```
输出#3
```
0
```

说明/提示

You can read about bitwise operations in https://en.wikipedia.org/wiki/Bitwise_operation.

Second sample:

Let $x$ be an input of the Petya's program. It's output is ((x&1)&3)&5=x&(1&3&5)=x&1 . So these two programs always give the same outputs.

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