How to calculate http://codeforces.net/predownloaded/72/22/72229c1ee97025cc5df1b89399cc826996bdc8f3.jpg this sum?↵
Constraints are 1 ≤ N, M ≤ 2·10^9, and 1 ≤ x ≤ 50.↵
Please can someone help?
Constraints are 1 ≤ N, M ≤ 2·10^9, and 1 ≤ x ≤ 50.↵
Please can someone help?