피보나치수

def solution(n):
    answer = 0
    
    before = 0; current = 1
    after = before + current #F(2)
    
    for i in range(n-2):
        before = current
        current = after
        after = before + current
        #print("after:", after, "= curret ", current , " + before ", before)
    
    answer = after%1234567
    
    
    return answer