from sys import stdin
 
def judge(filename, currYear):
    f = stdin
    n = int(f.readline())
    for i in range(n):
        Y = {}
        m = int(f.readline())
        for j in range(m):
            years = str.split(f.readline())
            start = int(years[0])
            stop = int(years[1] if len(years) > 1 else currYear)
            for k in range(start, stop+1):
                if k not in Y: Y[k] = 0
                Y[k] += 1
        x = max(Y.values())
        print sorted([y[0] for y in Y.items() if y[1] == x])
 
judge("judge.txt", 2015)

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

MgozCjE5MTAgMTk0OAoxOTQ4IDIwMTEKMTkyNyAxOTk1CjMKMTkxMCAxOTQ4CjE5MjcgMTk5NQoxOTQ1

2
3
1910 1948
1948 2011
1927 1995
3
1910 1948
1927 1995
1945