import sys n = int(input()) dic = {} for i in range(n) : key, value = map(int, input().split()) if key in dic : dic[key] += value else : dic[key] = value # 根据key进行排序 answer = sorted(dic.items(), key = lambda x:x[0]) # answer 的结果为[(0, 3), (1, 2), (3, 4)] # 遍历输出 for key in answer : print(str(key[0]) +...