import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes")
no = lambda :print("no");No = lambda :print("No")
#######################################################################
mod = 998244353


for _ in range(ni()):
    n, m = na()
    x = na()
    m2 = pow(m-2, mod-2, mod)
    ss = 0
    for i in range(n):
        if x[i] != -1:
            ss -= x[i]
        ss %= m

    if ss != 0:
        dpc = [1, 0, 0]
        dps = [0, 0, 0]
        s = 0
        for i in range(n):
            ndps, ndpc = [0, 0, 0], [0, 0, 0]
            dps, ndps = ndps, dps
            dpc, ndpc = ndpc, dpc
            if x[i] != -1:
                if s == 0:
                    dps[0] += ndps[0]
                else:
                    dps[0] += ndpc[0] + ndps[0]
                if (s + ss) % m == 0:
                    dps[1] += ndps[1]
                else:
                    dps[1] += ndpc[1] + ndps[1]
                if s == 0 or (s + ss) % m == 0:
                    dps[2] += ndpc[2] + ndps[2]
                else:
                    dps[2] += ndpc[2] * (m-3) % mod * m2 + ndps[2]
                dps[0] %= mod
                dps[1] %= mod
                dps[2] %= mod
                
                dpc[0] = ndpc[0]
                dpc[1] = ndpc[1]
                dpc[2] = ndpc[2]
            else:
                if s == 0:
                    dps[0] += ndps[0]
                    dps[1] += ndps[0]
                    dps[2] += ndps[0]
                else:
                    dps[0] += ndpc[0] + ndps[0]
                    dps[1] += ndpc[0] + ndps[0]
                    dps[2] += ndpc[0] + ndps[0]
                if (s + ss) % m == 0:
                    dps[0] += ndps[1]
                    dps[1] += ndps[1]
                    dps[2] += ndps[1]
                else:
                    dps[0] += ndpc[1] + ndps[1]
                    dps[1] += ndpc[1] + ndps[1]
                    dps[2] += ndpc[1] + ndps[1]
                if s == 0 or (s + ss) % m == 0:
                    dps[0] += ndpc[2] * (m-2) + ndps[2] * (m-2)
                    dps[1] += ndps[2] * (m-2) + ndpc[2] * (m-2)
                    dps[2] += ndps[2] * (m-2) + ndpc[2] * (m-2)
                else:
                    dps[0] += ndpc[2] * (m-3) + ndps[2] * (m-2)
                    dps[1] += ndpc[2] * (m-3) + ndps[2] * (m-2)
                    dps[2] += ndpc[2] * (m-3) + ndps[2] * (m-2)
                dps[0] %= mod
                dps[1] %= mod
                dps[2] %= mod

                dpc[0] = ndpc[0] + ndpc[1] + ndpc[2] * (m-2)
                dpc[1] = ndpc[0] + ndpc[1] + ndpc[2] * (m-2)
                dpc[2] = ndpc[0] + ndpc[1] + ndpc[2] * (m-2)
                dpc[0] %= mod
                dpc[1] %= mod
                dpc[2] %= mod
            if x[i] != -1:
                s += x[i]
            s %= m
        ans = dps[1]
    else:
        m1 = pow(m-1, mod-2, mod)
        dpc = [1, 0]
        dps = [0, 0]
        s = 0
        for i in range(n):
            ndps, ndpc = [0, 0], [0, 0]
            dps, ndps = ndps, dps
            dpc, ndpc = ndpc, dpc
            if x[i] != -1:
                if s == 0:
                    dps[0] += ndps[0]
                else:
                    dps[0] += ndpc[0] + ndps[0]
                if s == 0:
                    dps[1] += ndpc[1] + ndps[1]
                else:
                    dps[1] += ndpc[1] * (m-2) % mod * m1 + ndps[1]
                dps[0] %= mod
                dps[1] %= mod
                dpc[0] = ndpc[0]
                dpc[1] = ndpc[1]

            else:
                if s == 0:
                    dps[0] += ndps[0]
                    dps[1] += ndps[0]
                else:
                    dps[0] += ndpc[0] + ndps[0]
                    dps[1] += ndpc[0] + ndps[0]
                if s == 0:
                    dps[0] += ndpc[1] * (m-1) + ndps[1] * (m-1)
                    dps[1] += ndpc[1] * (m-1) + ndps[1] * (m-1)
                else:
                    dps[0] += ndpc[1] * (m-2) + ndps[1] * (m-1)
                    dps[1] += ndpc[1] * (m-2) + ndps[1] * (m-1)
                dps[0] %= mod
                dps[1] %= mod

                dpc[0] = ndpc[0] + ndpc[1] * (m-1)
                dpc[1] = ndpc[0] + ndpc[1] * (m-1)

                dpc[0] %= mod
                dpc[1] %= mod
            if x[i] != -1:
                s += x[i]
            s %= m
        ans = dps[0]
    print(ans%mod)