def cltime(A, i):
    return A[i][0] * 60 + A[i][1]

def numcame(A, i):
    s = 0
    for j in range(i):
        if abs(cltime(A, j) - cltime(A, i)) < 20:
            if A[j][3] == 1:
                continue
            else:
                s += 1
    return s

n = int(input())
A = []
for i in range(n):
    A.append(list(map(int, input().split())) + [0])
B = []
C = []
c = 0
time = 0
for i in range(n):
    if A[i][2] < numcame(A, i):
        A[i][3] = 1
        C.append(i)
for i in range(n):
    if not i in C:
        if cltime(A, i) < time:
            time += 20
            B.append([time // 60, time % 60])
        else:
            time = cltime(A, i) + 20
            B.append([time // 60, time % 60])
    else:
        B.append(A[i][:2])
for i in B:
    print(*i)