Problem:
Score: 100 points

Problem Statement

In AtCoder Kingdom, Gregorian calendar is used, and dates are written in the "year-month-day" order, or the "month-day" order without the year.

For example, May 3, 2018 is written as 2018-5-3, or 5-3 without the year.

In this country, a date is called Takahashi when the month and the day are equal as numbers. For example, 5-5 is Takahashi.

How many days from 2018-1-1 through 2018-a-b are Takahashi?

Constraints

a is an integer between 1 and 12 (inclusive).

b is an integer between 1 and 31 (inclusive).

2018-a-b is a valid date in Gregorian calendar.

Input

Input is given from Standard Input in the following format:

a b

Output

Print the number of days from 2018-1-1 through 2018-a-b that are Takahashi.

Sample Input 1

5 5

Sample Output 1

5

There are five days that are Takahashi: 1-1, 2-2, 3-3, 4-4 and 5-5.

Sample Input 2

2 1

Sample Output 2

1

There is only one day that is Takahashi: 1-1.

Sample Input 3

11 30

Sample Output 3

11

There are eleven days that are Takahashi: 1-1, 2-2, 3-3, 4-4, 5-5, 6-6, 7-7, 8-8, 9-9, 10-10 and 11-11.

Solution in Rust (1.15.1) (judge verdict: Runtime Error)

use std::io::*;
use std::str::FromStr;

fn read<T: FromStr>() -> T {
    let stdin = stdin();
    let stdin = stdin.lock();
    let token: String = stdin
        .bytes()
        .map(|c| c.expect("failed to read char") as char)
        .skip_while(|c| c.is_whitespace())
        .take_while(|c| !c.is_whitespace())
        .collect();
    token.parse().ok().expect("failed to parse token")
}

fn main() {
    const TARGET: char = '#';
    let h: u32 = read();
    let w: u32 = read();
    let board: Vec<Vec<char>> = (0..h).map(|_| read::<String>().chars().collect()).collect();
    let mut ans = "YES";
    for y in 0..h {
        for x in 0..w {
            if board[y as usize][x as usize] == TARGET {
                if ((y > 0 && board[(y as usize) - 1][x as usize] != TARGET)
                    || (y < h - 1 && board[(y as usize) + 1][x as usize] != TARGET)
                    || (x > 0 && board[y as usize][(x as usize) - 1] != TARGET)
                    || (x < w - 1 && board[y as usize][(x as usize) + 1] != TARGET))
                {
                    ans = "NO";
                }
            }
        }
    }
    println!("{}", ans)
}