PY

T=int(input())
def can_be_strictly_increasing(sequence):
    sorted_sequence = sorted(sequence)
    for i in range(1, len(sorted_sequence)):
        if sorted_sequence[i] == sorted_sequence[i - 1]:
            return False
    return True
for _ in range(T):
    n = int(input())
    sequence = list(map(int, input().split()))
    if can_be_strictly_increasing(sequence):
        print("YES")
    else:
        print("NO")