摘要：
You have an array: a1, a2, , an and you must answer for some queries. For each query, you are given an interval [L, R] and two numbers p and K. Your 阅读全文
摘要：
Problem Description One day, Touma Kazusa encountered a easy math problem. Given n and k, she need to calculate the following sum modulo 1e9+7.∑ni=1∑n 阅读全文