Create 1106. Parsing A Boolean Expression (#614)

Author: Chayandas07

1106. Parsing A Boolean Expression

@@ -0,0 +1,45 @@
+class Solution {
+public:
+    bool parseBoolExpr(string expression) {
+        
+        stack<char> st, op;
+
+        for(auto & it: expression){
+
+            if(it == '&' || it == '|' || it == '!'){
+                op.push(it);
+            }
+            else if(it == ')'){
+
+                int f = 0, t = 0;
+                while(st.top() != '('){
+                    char ch = st.top();
+                    if(ch == 'f') f++;
+                    if(ch == 't') t++;
+                    st.pop();
+                }
+
+                st.pop();
+
+                if(op.top() == '&'){
+                    if(f == 0) st.push('t');
+                    else st.push('f');
+                }
+                else if(op.top() == '|'){
+                    if(t > 0) st.push('t');
+                    else st.push('f');
+                }
+                else{
+                    if(f == 0) st.push('f');
+                    else st.push('t');
+                }
+                op.pop();
+            }
+            else{
+                st.push(it);
+            }
+        }
+
+        return st.top() == 'f' ? false : true;
+    }
+};