The Little Fish's Journey (Improved Version)

Problem Source

Luogu P1424

Problem Description

There is a little fish that swims $250$ kilometres every weekday and rests on weekends (a two-day weekend). Starting from week day $x$ and counting $n$ days ahead, how many kilometres will the little fish have swum in total?

Input Format

The input consists of two positive integers $x, n$: $n$ days are counted starting from week day $x$.

Output Format

Print one integer: the total distance the little fish has swum, in kilometres.

Sample Input

3 10

Sample Output

2000

Hint

The data guarantees $1\le x \le 7$ and $1 \le n\le 10^6$.