10972 - Remove unnecessary parentheses   

Description

Given an infix Boolean expression with parentheses, which has at most 4 variables ‘A’, ’B’, ‘C’, and ‘D’, and two operators ‘&’ and ‘|’. Please remove unnecessary parentheses and print the infix expression. Existence of unnecessary parentheses doesn’t affect the result of expression. For example,

(A&B)|(C&D) → A&B|(C&D)

(((A|B))) → A|B

Hint: You can combine two homework. Build a syntax tree and print the infix expression with necessary parentheses.

 

For OJ submission:

       Step 1. Submit your main.c into the submission block.(Please choose C compiler)

       Step 2. Check the results and debug your program if necessary.

 

Input

The input is an infix expression, which has at most 4 variables ‘A’, ’B’, ‘C’, and ‘D’, two operators ‘&’ and ‘|’, and parentheses. The length of the infix expression is less than 256.

Output

The output is an infix expression without unnecessary parentheses.

Sample Input  Download

Sample Output  Download

Tags

10402Contest



Discuss