n = int(input())
res_pattern = ''
for i in range(n):
pattern = input()
if i == 0:
res_pattern = list(pattern)
question_marks = [0] * len(res_pattern)
for j in range(len(pattern)):
if res_pattern[j] != pattern[j]:
if res_pattern[j] == "?":
res_pattern[j] = pattern[j]
elif pattern[j] == "?":
continue
else:
res_pattern[j] = "1"
else:
if res_pattern[j] == "?":
question_marks[j] += 1
for k in range(len(res_pattern)):
if res_pattern[k] == "1":
res_pattern[k] = "?"
if question_marks[k] == n:
res_pattern[k] = "x"
print("".join(res_pattern))
1301A - Three Strings | 460A - Vasya and Socks |
1624C - Division by Two and Permutation | 1288A - Deadline |
1617A - Forbidden Subsequence | 914A - Perfect Squares |
873D - Merge Sort | 1251A - Broken Keyboard |
463B - Caisa and Pylons | 584A - Olesya and Rodion |
799A - Carrot Cakes | 1569B - Chess Tournament |
1047B - Cover Points | 1381B - Unmerge |
1256A - Payment Without Change | 908B - New Year and Buggy Bot |
979A - Pizza Pizza Pizza | 731A - Night at the Museum |
742A - Arpa’s hard exam and Mehrdad’s naive cheat | 1492A - Three swimmers |
1360E - Polygon | 1517D - Explorer Space |
1230B - Ania and Minimizing | 1201A - Important Exam |
676A - Nicholas and Permutation | 431A - Black Square |
474B - Worms | 987B - High School Become Human |
1223A - CME | 1658B - Marin and Anti-coprime Permutation |