t = int(input()) for _ in range(t): n, k = map(int, input().split()) a = [0] + list(map(int, input().split()))

ans = 10**9
for color in range(1, 61):
    cnt = 0
    j = 1
    while j <= n:
        if a[j] != color:
            cnt += 1
            j += k
        else:
            j += 1
    ans = min(ans, cnt)

print(ans)