[Leetcode] Evaluate Reverse Polish Notation

Evaluate the value of an arithmetic expression in Reverse Polish Notation.

valid operators Are + ,  -,  * ,  /. Each operand is an integer or another expression.

Some Examples:

  ["2", "1", "+", "3", "*")--((2 + 1) (3)-9  ["4", "", "5", "/", "+"], 4 + (13/5))

public class Solution {public int evalrpn (string[] tokens) {stack<integer> Stack = new stack<integer> (); for (i NT i = 0; i < tokens.length; i++) {if (Tokens[i].equals ("+")) {int a = Stack.pop (); int b = Stack.pop (); int res = B + a;stack.push (res);} else if (token S[i].equals ("-")) {int a = Stack.pop (); int b = Stack.pop (); int res = B-a;stack.push (res);} else if (Tokens[i].equals ("*" ) {int a = Stack.pop (); int b = Stack.pop (); int res = b * A;stack.push (res);} else if (tokens[i].equals ("/")) {int a = Stack.pop (); int b = Stack.pop (); int res = B/a;stack.push (res);} else {Stack.pus H (Integer.parseint (Tokens[i]));}} return Stack.peek ();}}

[Leetcode] Evaluate Reverse Polish Notation