GCC '16 P3 - Hang Gliding Fun

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Points: 25 (partial)
Time limit: 1.0s
Java 8 1.4s
Memory limit: 256M

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Problem types

Bob lives in a city with N skyscrapers arranged in a row running north to south. He likes to hang glide over the city. Bob can glide south to a shorter building if all of the passed buildings' heights are smaller than his current building's height.

Each of the N buildings has height h_i, view value v_i, and danger value d_i for 1 \le i \le N. Bob has Q questions for you: Given that he starts at the B^{th} northmost building (1 \le B \le N), what is the maximum possible sum of the view values of buildings which he lands on such that none of those buildings has danger value more than M (1 \le M \le 10^6)?

Input Specification

The first line contains two space-separated numbers N (1 \le N \le 100\,000) and Q (1 \le Q \le 100\,000), the number of buildings and queries respectively.
The next N lines each contain h_i (1 \le h_i \le 10^6), v_i (1 \le v_i \le 10^6), and d_i (1 \le d_i \le 10^6), the height, view value, and danger value for the i^{th} northmost building.
The next Q lines each contain the query. Each line contains two space-separated numbers B (1 \le B \le N) and M (1 \le M \le 10^6). It is guaranteed that the danger value of the B^{th} northmost building is not more than M.

Output Specification

For each query, output the answer on a new line.

Sample Input 1

3 2
3 1 2
3 4 4
1 2 10
2 20
2 4

Sample Output 1

6
4

Explanation

For the first query, the path which maximizes the sum of view values is hang gliding to the third building, so the answer is 4+2. For the second query, the path which maximizes the sum of view values is simply staying put at the second building, so the answer is 4.


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