题解 | #合并表记录#

while True:
    try:
        n =int(input().strip())
    except EOFError:
        break
        
    nums = {}
    for i in range(n):
        k,v = map(int,input().strip().split())
        if nums.get(k):
            v = nums.get(k) + v
            nums.__setitem__(k, v)
        else:
            nums.__setitem__(k, v)
            
    min_k =min(nums.keys())
    
    while True:
        print(min_k,nums.get(min_k))
        nums.pop(min_k)
        if nums.keys():
            min_k =min(nums.keys())
        else:
            break