From 9fabcc111d79c9df621eca1108844fd0a5efc1a7 Mon Sep 17 00:00:00 2001
From: Matej Focko <me@mfocko.xyz>
Date: Sun, 20 Oct 2024 22:34:36 +0200
Subject: [PATCH] =?UTF-8?q?go:=20add=20=C2=AB1106.=20Parsing=20A=20Boolean?=
 =?UTF-8?q?=20Expression=C2=BB?=
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URL:	https://leetcode.com/problems/parsing-a-boolean-expression/
Signed-off-by: Matej Focko <me@mfocko.xyz>
---
 go/parsing-a-boolean-expression.go | 54 ++++++++++++++++++++++++++++++
 1 file changed, 54 insertions(+)
 create mode 100644 go/parsing-a-boolean-expression.go

diff --git a/go/parsing-a-boolean-expression.go b/go/parsing-a-boolean-expression.go
new file mode 100644
index 0000000..6fc3ae9
--- /dev/null
+++ b/go/parsing-a-boolean-expression.go
@@ -0,0 +1,54 @@
+package main
+
+import (
+	arraystack "github.com/emirpasic/gods/v2/stacks/arraystack"
+)
+
+func parseBoolExpr(expression string) bool {
+	getRune := func(result bool) rune {
+		if result {
+			return 't'
+		}
+		return 'f'
+	}
+
+	st := arraystack.New[rune]()
+
+	for _, token := range expression {
+		if token == ',' || token == '(' {
+			// ignore delimiters and opening brackets
+			continue
+		}
+
+		// Handle closing of the operation
+		if token == ')' {
+			hasTrue, hasFalse := false, false
+
+			for top, has := st.Peek(); has && top != '!' && top != '&' && top != '|'; top, has = st.Peek() {
+				if top == 't' {
+					hasTrue = true
+				} else if top == 'f' {
+					hasFalse = true
+				}
+				st.Pop()
+			}
+
+			// evaluate the operator
+			op, _ := st.Pop()
+			if op == '!' {
+				st.Push(getRune(!hasTrue))
+			} else if op == '&' {
+				st.Push(getRune(!hasFalse))
+			} else {
+				st.Push(getRune(hasTrue))
+			}
+
+			continue
+		}
+
+		st.Push(token)
+	}
+
+	result, _ := st.Peek()
+	return result == 't'
+}