Postfix-Notation (Stack)

Postfix_Notation.cpp

@@ -0,0 +1,52 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+int postfixEvaulation(string s)
+{
+  stack<int> st;
+  for (int i = 0; i < s.length(); i++)
+  {
+     if (s[i]>='0' && s[i]<='9')
+     st.push(s[i]-'0');  //-0 islye kiya for intiger value
+
+  else
+  {
+     int op2=st.top();
+     st.pop();
+     int op1=st.top();
+     st.pop();
+
+      switch (s[i])
+   {
+
+   case '+':
+       st.push(op1+op2);
+       break;
+
+   case '-':
+       st.push(op1-op2);
+       break;
+
+   case '*':1 
+       st.push(op1*op2);
+       break;
+
+   case '/':
+       st.push(op1/op2);
+       break;
+
+   case '^':
+       st.push(pow(op1,op2));
+       break;
+          }
+  }
+
+  }
+  return st.top();
+}
+
+int main()
+{
+    cout<<postfixEvaulation("46+2/5*7+")<<endl;
+    return 0;
+}