text: // An integer has sequential digits if and only if each digit in the number is one more than the previous digit.
  
  // Return a sorted list of all the integers in the range [low, high] inclusive that have sequential digits.
  
   
  
  // Example 1:
  
  // Input: low = 100, high = 300
  // Output: [123,234]
  // Example 2:
  
  // Input: low = 1000, high = 13000
  // Output: [1234,2345,3456,4567,5678,6789,12345]
   
  
  // Constraints:
  
  // 10 <= low <= high <= 10^9
  
  // solution: brute force
  
  class Solution {
  public:
      vector<int> sequentialDigits(int low, int high) {
          string s = "123456789";
          vector<int> v;
      
          for (int i = 0; i < s.length(); i++) {
              for (int j = i; j < s.length(); j++) {
                  string sub = s.substr(i, j-i+1);
                  int ans = stoi(sub);
              
                  if (ans >= low && ans <= high) {
                      v.push_back(ans);
                  }
              }
          }
      
          sort(v.begin(), v.end());
      
          return v;
      }
  };