Implement a calculator that evaluates expressions in Reverse Polish Notation (RPN), also known as Postfix notation.
In RPN, operators follow their operands. For example, "3 4 +" means "3 + 4 = 7".
The input will be a string containing numbers and operators separated by spaces. The operators are +, -, *, and /. Division should perform integer division (truncate towards zero).
Space-separated digits e.g. treat "54" as one number in "54 +"
Examples:
Input: "3 4 +" Output: 7 (3 + 4 = 7)
Input: "5 3 -" Output: 2 (5 - 3 = 2)
Input: "3 5 * 2 +" Output: 17 ((3 * 5) + 2 = 17)
Input: "7 2 / 3 +" Output: 6 ((7 / 2) + 3 = 6, integer division)
Apex Code Editor
Welcome to Lightning Challenge!
How It Works
- • Write your solution in the code editor
- • Connect your Salesforce org to test
- • Submit to check if your solution passes
- • Use hints if you get stuck
Contest Alert
🏆 #CodeEveryDay July 2026
Contest runs July 1 - 31. Complete challenges to climb the leaderboard!
Only the 31 daily challenges shown during this contest count toward points. Earlier dailies don't carry over.