n = int(input())
sub = {}
prsn = {}

for i in range(n):
    s = input().split()

    suma = 0
    for j in range(1, len(s)):
        x, y = s[j].split(':')
        y = float(y)
        suma += y

        if x not in sub:
            sub.update({x: [y, 1]})
        else:
            sub[x][0] += y
            sub[x][1] += 1

    prsn.update({s[0]: suma/(len(s)-1)})

for i in sorted(prsn.keys()):
    print(i, prsn[i])

for i in sorted(sub.keys()):
    print(i, sub[i][0]/sub[i][1])