fix: do not find substring with length 1 and print test case after updating result

1_longest_substring_with_k_distinct_characters.cpp

@@ -107,7 +107,8 @@ result find(const std::string &s, const unsigned long k) {
       start++;
     }
     if (char_count.size() == k &&
-        end - start > r.longest_end - r.longest_start) {
+        (end - start > r.longest_end - r.longest_start ||
+         r.match_found == false)) {
       r.longest_start = start, r.longest_end = end;
       r.match_found = true;
     }
@@ -170,30 +171,30 @@ int main(int argc, char *argv[]) {
         << std::endl;
     random_number_generator<unsigned int> random_ascii_char(97, 122); // a-z
     random_number_generator<unsigned int> rng;
-    for (unsigned int i = 0; i < 1; i++) {
+    for (unsigned int i = 0; i < 10; i++) {
       test_case t;
       t.i.s += (char)random_ascii_char();
-      std::cout << t;
       t.r = find(t.i.s, t.i.k);
+      std::cout << t;
       for (unsigned int j = 0; j < 10; j++) {
         for (unsigned int k = 0, increase_str_len_by = rng(100, 1000);
              k < increase_str_len_by; k++) {
           t.i.s += (char)random_ascii_char();
-          std::cout << t;
           result r = find(t.i.s, t.i.k);
           if (r.match_found && t.r.match_found)
             assert(r.longest_end - r.longest_start >=
                    t.r.longest_end - t.r.longest_start);
           t.r = r;
+          std::cout << t;
           assert(K_verify(t));
         }
         while (t.r.match_found) {
-          std::cout << t;
           result r = find(t.i.s, ++t.i.k);
           if (r.match_found)
             assert(r.longest_end - r.longest_start >=
                    t.r.longest_end - t.r.longest_start);
           t.r = r;
+          std::cout << t;
           assert(K_verify(t));
         }
         t.i.k = rng(1, --t.i.k);