I used dictionary in python 2.7 to solve this problem, but got MLE on test#21. Can anybody give me some advise or hint about how to deal with this problem? Thanks a lot!!!

Here is my code:

from sys import stdin

num = int(stdin.readline())
notes = {}
for i in range(num):
    key = int(stdin.readline().strip())
    if notes.has_key(key):
        notes[key] += 1
    else:
        notes[key] = 1
max = -1
note = -1
for key, value in notes.items():
    if value > max:
        note = key
        max = value
print note

I have MLE too :(

def main():

    import sys
    from collections import Counter
    n = raw_input()
    lns = sys.stdin.readlines()
    cnt = Counter(lns)
    print max(cnt, key=cnt.get)[:-1]

main()