def main():
    inp = int(input())
    num = ""
    count = 0
    
    loop_flg = True 
 
    while loop_flg:
        num = num + "9"
        count += 1
        if int(num) % inp == 0:
            loop_flg = False
        
    print(count)
    
if __name__ == '__main__':
    main()