HDU 2178 guess number

To guess the maximum number M, that is to say, you can guess every number between 1 and M in n times! Http://hi.baidu.com/xiao%5Fyu%5Ffeng/blog/item/11ab800ed1a7a3236159f334.html

Therefore, in the worst case, you only need to guess log2 (m) + 1 (integer) at most between 1 and M, so Yi Zhi => m = 2 ^ n-1. that is, you can guess n times. The maximum number you can guess is 2 ^ n-1. we can also think that we can guess within n times between 1 and 2 ^ n-1. If it is greater than this number, we may not be able to guess it within n times. For example, we have to guess at least three times between 1 and 7.

# Include <stdio. h> int main () {int t, n, m; scanf ("% d", & T); While (t --) {scanf ("% d ", & N); M = 1; while (n --) m <= 1; printf ("% d \ n" m-1);} return 0 ;}