t=int(input())



for T in range(t):



    n=int(input())

    a=list(map(int,input().split()))

    a.sort()

    flag=0

    for i in range(n-1):

        if(abs(a[i]-a[i+1])>1):

            print("NO")

            flag=1



            break

    if(flag==0):

        print("YES")
a67de3d29a1ec84aacbe425a7dbfb133bc38bb6d
<mask token>

<mask token>
for T in range(t):
    n = int(input())
    a = list(map(int, input().split()))
    a.sort()
    flag = 0
    for i in range(n - 1):
        if abs(a[i] - a[i + 1]) > 1:
            print('NO')
            flag = 1
            break
    if flag == 0:
        print('YES')

t = int(input())
for T in range(t):
    n = int(input())
    a = list(map(int, input().split()))
    a.sort()
    flag = 0
    for i in range(n - 1):
        if abs(a[i] - a[i + 1]) > 1:
            print('NO')
            flag = 1
            break
    if flag == 0:
        print('YES')

t=int(input())



for T in range(t):



    n=int(input())

    a=list(map(int,input().split()))

    a.sort()

    flag=0

    for i in range(n-1):

        if(abs(a[i]-a[i+1])>1):

            print("NO")

            flag=1



            break

    if(flag==0):

        print("YES")