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Amit-S-Sahu · Oct 20, 2024 · a66b6a9 · a66b6a9
1 parent 97fec8d
commit a66b6a9
Showing 1 changed file with 28 additions and 0 deletions.
diff --git a/1106-parsing-a-boolean-expression/1106-parsing-a-boolean-expression.java b/1106-parsing-a-boolean-expression/1106-parsing-a-boolean-expression.java
@@ -0,0 +1,28 @@
+class Solution {
+    public boolean parseBoolExpr(String expression) {
+        Stack<Character> operator = new Stack<>();
+        Stack<Character> operands = new Stack<>();
+
+        for (int i = 0; i < expression.length(); i++) {
+            char curr = expression.charAt(i);
+
+            if (curr == '!' || curr == '&' || curr == '|') operator.push(curr);  
+            else if (curr == '(') operands.push(curr);  
+            else if (curr == 'f') operands.push('0');   
+            else if (curr == 't') operands.push('1');   
+            else if (curr == ')') {
+                char op = operator.pop();
+                int res = (operands.pop() - '0');  
+
+                while (operands.peek() != '(') {
+                    if (op == '&') res &= (operands.pop() - '0');  
+                    else if (op == '|') res |= (operands.pop() - '0');
+                }
+                operands.pop();
+                if (op == '!') res = res == 1 ? 0 : 1;
+                operands.push((char)(res + '0'));
+            }
+        }
+        return operands.pop() == '1';
+    }
+}