|2016-2017 ACM-ICPC, NEERC, Southern Subregional Contest (Online Mirror, ACM-ICPC Rules, Teams Preferred)|
Polycarp starts his own business. Tomorrow will be the first working day of his car repair shop. For now the car repair shop is very small and only one car can be repaired at a given time.
Polycarp is good at marketing, so he has already collected n requests from clients. The requests are numbered from 1 to n in order they came.
The i-th request is characterized by two values: s i — the day when a client wants to start the repair of his car, d i — duration (in days) to repair the car. The days are enumerated from 1, the first day is tomorrow, the second day is the day after tomorrow and so on.
Polycarp is making schedule by processing requests in the order from the first to the n-th request. He schedules the i-th request as follows:
Given n requests, you are asked to help Polycarp schedule all of them according to the rules above.
The first line contains integer n (1 ≤ n ≤ 200) — the number of requests from clients.
The following n lines contain requests, one request per line. The i-th request is given as the pair of integers s i, d i (1 ≤ s i ≤ 109, 1 ≤ d i ≤ 5·106), where s i is the preferred time to start repairing the i-th car, d i is the number of days to repair the i-th car.
The requests should be processed in the order they are given in the input.
Print n lines. The i-th line should contain two integers — the start day to repair the i-th car and the finish day to repair the i-th car.