s0038

src/s0038_count_and_say.cpp

@@ -0,0 +1,21 @@
+#include "s0038_count_and_say.hpp"
+
+string Solution::countAndSay(int n) {
+  if (n == 1) {
+    return "1";
+  } else if (n <= 0) {
+    return "";
+  }
+  string prev = countAndSay(n - 1);
+  string result{""};
+  int len = prev.length();
+  int pos{0}, start{0};
+  while (pos < len) {
+    while (pos < len && prev[pos] == prev[start]) {
+      pos++;
+    }
+    result += to_string(pos - start) + prev[start];
+    start = pos;
+  }
+  return result;
+}