Survivor's blog

By Survivor, history, 7 years ago, In English

link to spoj problem "blamoeba" i need help to complete this problem. i am stuck since last 2 days. solution was easy but i am not getting how to use modular inverse to calculate the final answer. answer — y/x = (m-1)*(m^n)/(m^n-1) (where m^n means m to the power n). how to calculate the gcd of numerator and denominator before using modulo ?
according to me the answer should be

x = (m^n-1)/gcd
y = (m-1)*(m^n)/gcd

help me to do this or correct me if i am doing something wrong
thanks in advance

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7 years ago, # |
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7 years ago, # |
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mn - 1 = (m - 1)(mn - 1 + mn - 2 + ... + m + 1)

So mn - 1 is always divisible by m - 1. And gcd(mn - 1, mn) = 1.

It can be calculated in time.