import java.io.*; import java.util.*; import java.util.stream.*; public class Main { public static void main(String[] args) throws Exception { Scanner sc = new Scanner(); int t = sc.nextInt(); StringBuilder sb = new StringBuilder(); while (t-- > 0) { int n = sc.nextInt(); char[] inputs = sc.next().toCharArray(); long[][] hashes = new long[10][n]; for (int i = 0; i < n; i++) { hashes[0][i] = inputs[i] - 'a'; } for (int i = 1; i < 10; i++) { for (int j = 0; j + i < n; j++) { hashes[i][j] = hashes[i - 1][j] * 26 + hashes[0][j + i]; } } int ans = 0; for (int i = 1; i < n; i++) { int left = i; int right = n - i; int idx = 0; boolean decided = false; while (left - idx > 0 && right - idx> 0) { int length = Math.min(10, Math.min(left - idx, right - idx)); if (hashes[length - 1][0 + idx] == hashes[length - 1][i + idx]) { idx += 10; } else if (hashes[length - 1][0 + idx] < hashes[length - 1][i + idx]) { ans++; decided = true; break; } else { decided = true; break; } } if (!decided) { if (left < right) { ans++; } } } sb.append(ans).append("\n"); } System.out.print(sb); } } class Utilities { static String arrayToLineString(Object[] arr) { return Arrays.stream(arr).map(x -> x.toString()).collect(Collectors.joining("\n")); } static String arrayToLineString(int[] arr) { return String.join("\n", Arrays.stream(arr).mapToObj(String::valueOf).toArray(String[]::new)); } } class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); StringBuilder sb = new StringBuilder(); public Scanner() throws Exception { } public int nextInt() throws Exception { return Integer.parseInt(next()); } public long nextLong() throws Exception { return Long.parseLong(next()); } public double nextDouble() throws Exception { return Double.parseDouble(next()); } public int[] nextIntArray() throws Exception { return Stream.of(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); } public String next() throws Exception { while (!st.hasMoreTokens()) { st = new StringTokenizer(br.readLine()); } return st.nextToken(); } }