合并表记录(Python3解答）

while True:
    try:
        a=int(input())
        dic = {}
        for i in range(a):
            key, val = input().split()
            key = int(key)
            val = int(val)
            if key in dic:
                dic[key] += val
            else:
                dic[key] = val
        for i in sorted(dic.keys()):
            print(str(i)+" "+str(dic[i]))
    except:
        break