[python] 백준 : 사탕 선생 고창영 (2547번)

t = int(input())
for i in range(t):
    total = 0
    input()
    n = int(input())
    for j in range(n):
        candy = int(input())
        total += candy
    if total % n == 0:
        print("YES")
    else:
        print("NO")