|
| 1 | +#!/usr/bin/python3 |
| 2 | +""" |
| 3 | +A valid parentheses string is either empty (""), "(" + A + ")", or A + B, where |
| 4 | +A and B are valid parentheses strings, and + represents string concatenation. |
| 5 | +For example, "", "()", "(())()", and "(()(()))" are all valid parentheses strings. |
| 6 | +
|
| 7 | +A valid parentheses string S is primitive if it is nonempty, and there does not |
| 8 | +exist a way to split it into S = A+B, with A and B nonempty valid parentheses |
| 9 | +strings. |
| 10 | +
|
| 11 | +Given a valid parentheses string S, consider its primitive decomposition: |
| 12 | +S = P_1 + P_2 + ... + P_k, where P_i are primitive valid parentheses strings. |
| 13 | +
|
| 14 | +Return S after removing the outermost parentheses of every primitive string in |
| 15 | +the primitive decomposition of S. |
| 16 | +
|
| 17 | +Example 1: |
| 18 | +Input: "(()())(())" |
| 19 | +Output: "()()()" |
| 20 | +Explanation: |
| 21 | +The input string is "(()())(())", with primitive decomposition "(()())" + "(())". |
| 22 | +After removing outer parentheses of each part, this is "()()" + "()" = "()()()". |
| 23 | +
|
| 24 | +Example 2: |
| 25 | +Input: "(()())(())(()(()))" |
| 26 | +Output: "()()()()(())" |
| 27 | +Explanation: |
| 28 | +The input string is "(()())(())(()(()))", with primitive decomposition |
| 29 | +"(()())" + "(())" + "(()(()))". |
| 30 | +After removing outer parentheses of each part, this is "()()" + "()" + |
| 31 | +"()(())" = "()()()()(())". |
| 32 | +
|
| 33 | +Example 3: |
| 34 | +Input: "()()" |
| 35 | +Output: "" |
| 36 | +Explanation: |
| 37 | +The input string is "()()", with primitive decomposition "()" + "()". |
| 38 | +After removing outer parentheses of each part, this is "" + "" = "". |
| 39 | +
|
| 40 | +
|
| 41 | +Note: |
| 42 | +S.length <= 10000 |
| 43 | +S[i] is "(" or ")" |
| 44 | +S is a valid parentheses string |
| 45 | +""" |
| 46 | +fromcollectionsimportdeque |
| 47 | + |
| 48 | + |
| 49 | +classSolution: |
| 50 | +defremoveOuterParentheses(self,S:str)->str: |
| 51 | +""" |
| 52 | + Primitive parentheses will have equal number of opened and closed |
| 53 | + parentheses. |
| 54 | +
|
| 55 | + Use count |
| 56 | + Exclude the first and last parathesis |
| 57 | + """ |
| 58 | +ret= [] |
| 59 | +cnt=0 |
| 60 | +foreinS: |
| 61 | +ife=="(": |
| 62 | +cnt+=1 |
| 63 | +ifcnt>1: |
| 64 | +ret.append(e) |
| 65 | +else: |
| 66 | +cnt-=1 |
| 67 | +ifcnt>0: |
| 68 | +ret.append(e) |
| 69 | + |
| 70 | +return"".join(ret) |
| 71 | + |
| 72 | + |
| 73 | +defremoveOuterParentheses_error(self,S:str)->str: |
| 74 | +""" |
| 75 | + stack + deque |
| 76 | + """ |
| 77 | +ret= [] |
| 78 | +stk= [] |
| 79 | +cur_q=deque() |
| 80 | +foreinS: |
| 81 | +ife=="(": |
| 82 | +stk.append(e) |
| 83 | +else: |
| 84 | +prev=stk.pop() |
| 85 | +ifstk: |
| 86 | +cur_q.appendleft(prev) |
| 87 | +cur_q.append(e) |
| 88 | +else: |
| 89 | +ret.extend(cur_q) |
| 90 | +cur_q=deque() |
| 91 | + |
| 92 | +return"".join(ret) |
| 93 | + |
| 94 | + |
| 95 | +if__name__=="__main__": |
| 96 | +assertSolution().removeOuterParentheses("(()())(())(()(()))")=="()()()()(())" |