2652：Warching TV

Lemon likes warching TV very much. When winter holiday comes, it is a good time, isn’t it. There are lots of TV program listed on the paper. Every TV program has its start time ,end time, and the happiness value that will add Lemon’s happiness and it depends on Lemon’s taste.

There are many test cases. Please process to end of file. Each test case starts with one integer N (1 <= N <= 100000) which indicates the size of the list of the TV program. Then N lines follow, each line contains three integers s, e and v. s, e indicate that the TV program is during [s, e](1 <= s <= e <= 1000000). v indicates that after warching the TV program will add Lemon v happyiness(1 <= v <= 1000). Once Lemon choose a TV program, he must finish warching the TV program.

Print the maximum happiness value that Lemon will get.