题解 | #合并表记录#

n=int(input())
dic=dict()
for _ in range(n):
    k,v=list(map(lambda x:int(x),input().split()))
    if k in dic:
        dic[k]+=v
    else:
        dic[k]=v
keys=sorted(dic.keys())
res=[(key,dic[key]) for key in keys]
for item in res:
    k,v=item
    print(k,v)