message: Update minimum-costs-using-the-train-line.cpp
diff: @@ -6,7 +6,7 @@ class Solution {
  public:
  vector<long long> minimumCosts(vector<int>& regular, vector<int>& express, int expressCost) {
  vector<long long> result;
  - vector<long long> dp = {0, expressCost};
  + vector<long long> dp = {0, expressCost}; // dp[0]: min cost of regular route to curr stop, dp[1]: min cost of express route to curr stop
  for (int i = 0; i < size(regular); ++i) {
  dp = {min(dp[0] + regular[i], dp[1] + express[i]),
  min(dp[0] + regular[i] + expressCost, dp[1] + express[i])};
  