import sys

sys.setrecursionlimit(200005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
# dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

# md = 10**9+7
md = 998244353

from collections import defaultdict

def solve():
    n, m = LI()
    xx = LI()
    l = r = -1
    c = 0
    for i, x in enumerate(xx):
        if x == -1:
            if l == -1: l = i
            r = i
            c += 1
    if c == 0:
        ans = n
        s = 0
        for x in xx:
            s += x
            s %= m
            if s == 0: ans -= 1
        if s: print(0)
        else: print(ans)

        return
    ans = (n-1)*pow(m, c-1, md)%md

    p = pow(m, c-1, md)
    s = 0
    for i in range(l):
        s += xx[i]
        s %= m
        if s == 0:
            ans -= p
            ans %= md
    s = 0
    for i in range(n-1, r, -1):
        s += xx[i]
        s %= m
        if s == 0:
            ans -= p
            ans %= md

    if c>1:ans -= pow(m, c-2, md)*(r-l)%md
    print(ans%md)

for _ in range(II()): solve()