数学题(2)——求数学期望
F.Kevin and Expected Value Time Limit: 1000 MS Memory Limit: 65536 K Total Submit: 70 (26 users) Total Accepted: 25 (24 users) Special Judge: No Description Kevinsogo is a professor of mathematics, One day he gave an assignment to his students which was hard for them. The students want you to help them in solving the problem.
Given the value of N, X = rand( ) mod N
Note that rand() returns an integer between 0 and 10^100 (inclusive) uniformly at random.