def ileCiastekZjeObzartuch(number):
    return math.floor(24*3600/number)
ileCiastek=[]
wynik=[]
inp=int(input())
counterTable=[]
for item in range(inp):#ile przypadkow
    numbers=input().split()
    for i in range(int(numbers[0])):#ile obzartuchow
        sum=0
        obzartuchTempo = int(input())
        ileCiastek.append(ileCiastekZjeObzartuch(obzartuchTempo))
    for it in ileCiastek:
        sum+=it
    ileCiastek=[]
    wynik.append(math.ceil(sum/int(numbers[1])))
for item in wynik:
    print(item)

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

MgoyIDEwCjM2MDAKMTgwMAozIDM1NgoxMjMKMzI5OTkKMTAxMDE=

2
2 10
3600
1800
3 356
123
32999
10101