from sys import stdin
input = stdin.readline

MOD = 998244353

for _ in range(int(input())):
    N, M = map(int, input().split())
    X = list(map(int, input().split()))

    cnt = X.count(-1)
    if cnt <= 1:
        if cnt == 1:
            SUM = 0
            for x in X:
                if x != -1:
                    SUM += x
                    SUM %= M
            X[X.index(-1)] = (M-SUM)%M
        else:
            if sum(X)%M != 0:
                print(0)
                continue
        ans = 0
        SUM = 0
        for x in X:
            SUM += x
            SUM %= M
            if SUM != 0:
                ans += 1
        print(ans)
        continue

    POW = [1]
    for _ in range(N):
        POW.append(POW[-1]*M%MOD)

    leftC = 0
    leftS = 0
    rightC = 0
    rightS = 0
    for x in X:
        if x == -1:
            rightC += 1
        else:
            rightS += x
            rightS %= M
    
    ans = 0
    for x in X:
        if x == -1:
            rightC -= 1
            if 1 <= rightC:
                ans += POW[leftC]*(M-1)%MOD*POW[rightC-1]%MOD
                ans %= MOD
            else:
                if rightS != 0:
                    ans += POW[leftC]
                    ans %= MOD
            leftC += 1
        else:
            rightS -= x
            if 1 <= rightC:
                if 1 <= leftC:
                    ans += POW[leftC-1]*(M-1)%MOD*POW[rightC-1]%MOD
                    ans %= MOD
                else:
                    if (leftS+x)%M != 0:
                        ans += POW[rightC-1]
                        ans %= MOD
            else:
                if rightS != 0:
                    ans += POW[leftC-1]
                    ans %= MOD
            leftS += x
    
    print(ans)