D. Skills
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Gladwell said it takes $$$10,000$$$ hours to master a skill. Bob disagrees and says he only needs $$$N$$$ hours. Bob wants to know how many days it will take him to master $$$M$$$ skills, assuming that he can practice $$$\textbf{each}$$$ skill for at most $$$\textbf{2 hours a day}$$$ and he needs to sleep $$$\textbf{8 hours a day}$$$.

Input

The first line contains two integers, $$$N$$$ $$$(1 \leq N \lt 10^4)$$$ and $$$M$$$ $$$(1 \leq M \leq 10^6)$$$.

Output

Print the number of days it takes Bob to master all M skills.

Examples
Input
10 2
Output
5
Input
5 4
Output
3