### aya1909's blog

By aya1909, history, 4 days ago,

Given a range [l r] find the sum of last digits of fibonacci numbers between l and r. i.e , last(fib(l))+last(fib(l+1)) .... last(fib(r)),

where last(fib(a)) denotes last digit of ath fibonacci number.

1<=l<=r<=1e9

• 0

 » 4 days ago, # |   0 one property of fibonacci number is last digit repeats at an interval of 60 .i think this will help.
 » 4 days ago, # | ← Rev. 2 →   0 Using Pisano Period for $base = 10$ then we have $\pi(n) = 60$ numbers per cycle