def get_z(s):
    n = len(s)
    Z = [0] * n
    Z[0] = n
    l, r = 0, 0
    for i in range(1, n):
        if i <= r:
            Z[i] = min(r - i + 1, Z[i - l])
        while i + Z[i] < n and s[Z[i]] == s[i + Z[i]]:
            Z[i] += 1
        if i + Z[i] - 1 > r:
            l, r = i, i + Z[i] - 1
    return Z

def solve():
    import sys
    input = sys.stdin.read().split()
    idx = 0
    T = int(input[idx])
    idx += 1
    for _ in range(T):
        N = int(input[idx])
        idx += 1
        S = input[idx]
        idx += 1
        Z = get_z(S)
        count = 0
        for i in range(N - 1):
            start = i + 1
            len_u = i + 1
            len_v = N - start
            m = min(len_u, len_v)
            z_val = Z[start] if start < N else 0
            lcp = min(z_val, m)
            if lcp < m:
                if S[lcp] < S[start + lcp]:
                    count += 1
            else:
                if len_u < len_v:
                    count += 1
        print(count)

if __name__ == '__main__':
    solve()