题解 | #走方格的方案数#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNextInt()) { // 注意 while 处理多个 case
            int a = in.nextInt();
            int b = in.nextInt();
            System.out.print(recur(1, 1, b+1, a+1));
        }
    }
    public static int recur(int start, int end, int width, int heigh) {
        if (start == width || end == heigh) {
            return 1;
        } else {
            return recur(start+1, end, width, heigh) + recur(start, end+1, width, heigh);

        }
    }
}