题解 | #走方格的方案数#

import java.util.Scanner;

/**
 * @author zq
 */
public class Main {
    //走方格的方案数
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
       
        while (scanner.hasNextInt()){
          int  m = scanner.nextInt();
           int n = scanner.nextInt();
            //分析可得：n>1.m>1时是不断求直到n=1或者m=1，
            // 此时路径数等于m+n
            System.out.println(lu(m, n));
        }
        

    }
    public static int lu(int m,int n){
        if ((n==1&&m>=1)||(m==1&&n>=1)){
            return m+n;
        }
        return lu(m,n-1)+lu(m-1,n);
    }

    
}