Solution to 1021

Author: Indigo2233

src/unresolved/1021.remove-outermost-parentheses.jl renamed to src/problems/1021.remove-outermost-parentheses.jl

@@ -1,8 +1,8 @@
 # ---
 # title: 1021. Remove Outermost Parentheses
 # id: problem1021
-# author: Tian Jun
-# date: 2020-10-31
+# author: Indigo
+# date: 2022-03-19
 # difficulty: Easy
 # categories: Stack
 # link: <https://leetcode.com/problems/remove-outermost-parentheses/description/>
@@ -73,5 +73,14 @@
 ## @lc code=start
 using LeetCode
 
-## add your code here:
+function remove_outer_parentheses(s::String)
+    res = ""    
+    cnt = 0
+    for ch in s
+        flg = cnt < 0
+        cnt += ch == '(' ? -1 : 1
+        (flg && cnt < 0) && (res *= ch)
+    end
+    return res
+end
 ## @lc code=end

test/problems/1019.next-greater-node-in-linked-list.jl

@@ -1,6 +1,6 @@
 @testset "1019.next-greater-node-in-linked-list.jl" begin
     @test next_larger_nodes(ListNode{Int}([1, 7, 5, 1, 9, 2, 5, 1])) ==
-        [7, 9, 9, 9, 0, 5, 0, 0]
+          [7, 9, 9, 9, 0, 5, 0, 0]
     @test next_larger_nodes(ListNode{Int}([2, 7, 4, 3, 5])) == [7, 0, 5, 5, 0]
     @test next_larger_nodes(ListNode{Int}([2, 1, 5])) == [5, 5, 0]
 end

test/problems/1021.remove-outermost-parentheses.jl

@@ -0,0 +1,5 @@
+@testset "1021.remove-outermost-parentheses.jl" begin
+    @test remove_outer_parentheses("(()())(())(()(()))") == "()()()()(())"
+    @test remove_outer_parentheses("(()())(())") == "()()()"
+    @test remove_outer_parentheses("()()") == ""
+end