while True:
n,m = map(int,input().split())
if n + m == 0:
break
L = []
for i in range(n):
L.append(list(map(int,input().split())))
d = {}
for i in L:
for j in i:
try:
d[j]+=1
except:
d[j] = 1
d = list(d.items())
d.sort(key = lambda t : -t[1])
ret = [i[0] for i in d if i[1] == d[1][1]]
print(" ".join(list(map(str, sorted(ret)))))