#!/usr/bin/env python
# -*- coding: utf-8 -*-


def kadomatsu(a, b):
    if b > a:
        sm = a - 1
        sm += b - a - 1
        print(sm)

    else:
        sm = 1999999999 - b
        print(sm)


def main():
    a, b = map(int, input().split())
    kadomatsu(a, b)


if __name__ == '__main__':
    main()