codeforcesRound#260(div2)A解题报告

Input The first line contains an integer n ( 1?≤? n ?≤?10 5 ) — the number of laptops. Next n lines contain two integers each, a i and b i (1?≤? a i ,? b i ?≤? n ) , where a i is the price of the i -th laptop, and b i is the number th

Input

The first line contains an integer n (1?≤?n?≤?105) — the number of laptops.

Next n lines contain two integers each, ai and bi (1?≤?ai,?bi?≤?n), where ai is the price of the i-th laptop, and bi is the number that represents the quality of the i-th laptop (the larger the number is, the higher is the quality).

All ai are distinct. All bi are distinct.