题解 | #合并表记录#

n = int(input())
l = []
ll = set()
for i in range(n):
    s = input()
    s = list(map(int,s.split()))
    k = int(s[0])
    ll.add(k)
    t = (k,int(s[1]))
    l.append(t)
for k in sorted(ll):
    v = 0
    for t in l:
        if t[0]==k:
            v += t[1]
    print(k,v)