misc: Fix aylei#3

Author: hzlinqien

src/problem.rs

@@ -3,8 +3,8 @@ extern crate reqwest;
 
 use std::fmt::{Display, Formatter, Error};
 
-const PROBLEMS_URL: &str = "https://leetcode.com/api/problems/algorithms/";
-const GRAPHQL_URL: &str = "https://leetcode.com/graphql";
+const PROBLEMS_URL: &str = "https://leetcode-cn.com/api/problems/algorithms/";
+const GRAPHQL_URL: &str = "https://leetcode-cn.com/graphql";
 const QUESTION_QUERY_STRING: &str = r#"
 query questionData($titleSlug: String!) {
     question(titleSlug: $titleSlug) {
@@ -20,7 +20,7 @@ const QUESTION_QUERY_OPERATION: &str = "questionData";
 pub fn get_problem(id: u32) -> Option<Problem> {
     let problems = get_problems().unwrap();
     for problem in problems.stat_status_pairs.iter() {
-        if problem.stat.question_id == id {
+        if problem.stat.frontend_question_id == id {
             let client = reqwest::Client::new();
             let resp: RawProblem = client.post(GRAPHQL_URL)
                 .json(&Query::question_query(problem.stat.question_title_slug.as_ref().unwrap()))