tomatocream
1dec88aaf2
Add populate-notes.mjs that fetches problem descriptions and Python/C++ code stubs from LeetCode's GraphQL API. Populated all 197 NeetCode 150 note files with: - Problem description (examples, constraints) - Python code stub (function signature) - C++ code stub (function signature + includes) API responses cached in leetcode/.cache/leetcode/ for instant re-runs.
1.8 KiB
1.8 KiB
TODO 0150. Evaluate Reverse Polish Notation medium
You are given an array of strings tokens that represents an arithmetic expression in a Reverse Polish Notation.
Evaluate the expression. Return an integer that represents the value of the expression.
Note that:
- The valid operators are
'+','-','*', and'/'. - Each operand may be an integer or another expression.
- The division between two integers always truncates toward zero.
- There will not be any division by zero.
- The input represents a valid arithmetic expression in a reverse polish notation.
- The answer and all the intermediate calculations can be represented in a 32-bit integer.
Example 1:
Input: tokens = ["2","1","+","3","*"]
Output: 9
Explanation: ((2 + 1) * 3) = 9Example 2:
Input: tokens = ["4","13","5","/","+"]
Output: 6
Explanation: (4 + (13 / 5)) = 6Example 3:
Input: tokens = ["10","6","9","3","+","-11","*","/","*","17","+","5","+"]
Output: 22
Explanation: ((10 * (6 / ((9 + 3) * -11))) + 17) + 5
= ((10 * (6 / (12 * -11))) + 17) + 5
= ((10 * (6 / -132)) + 17) + 5
= ((10 * 0) + 17) + 5
= (0 + 17) + 5
= 17 + 5
= 22Constraints:
1 <= tokens.length <= 10^{4}tokens[i]is either an operator:"+","-","*", or"/", or an integer in the range[-200, 200].
TODO Approach
Write your approach here.
TODO Python
class Solution:
def evalRPN(self, tokens: List[str]) -> int:TODO C++
class Solution {
public:
int evalRPN(vector<string>& tokens) {
}
};