t = int(input())
for _ in range(t):
n = int(input())
seq = [int(n) for n in input().split()]
seq.sort()
ans = "YES"
for i in range(len(seq) - 1):
if(seq[i] == seq[i + 1]): ans = "NO"
print(ans)264A - Escape from Stones | 1506A - Strange Table |
456A - Laptops | 855B - Marvolo Gaunt's Ring |
1454A - Special Permutation | 1359A - Berland Poker |
459A - Pashmak and Garden | 1327B - Princesses and Princes |
1450F - The Struggling Contestant | 1399B - Gifts Fixing |
1138A - Sushi for Two | 982C - Cut 'em all |
931A - Friends Meeting | 1594A - Consecutive Sum Riddle |
1466A - Bovine Dilemma | 454A - Little Pony and Crystal Mine |
2A - Winner | 1622B - Berland Music |
1139B - Chocolates | 1371A - Magical Sticks |
1253A - Single Push | 706B - Interesting drink |
1265A - Beautiful String | 214A - System of Equations |
287A - IQ Test | 1108A - Two distinct points |
1064A - Make a triangle | 1245C - Constanze's Machine |
1005A - Tanya and Stairways | 1663F - In Every Generation |