题解 | #走方格的方案数#

import java.util.*;

// 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);
        while (in.hasNext()) {
            String[] str = in.nextLine().split(" ");
            int n = Integer.parseInt(str[0]);
            int m = Integer.parseInt(str[1]);
            int[][] dp = new int[n + 1][m + 1];
            for (int i = 0; i < n + 1; i++) {
                dp[i][0] = 1;
            }
            Arrays.fill(dp[0], 1);
            for (int i = 1; i < n + 1; i++) {
                for (int j = 1; j < m + 1; j++) {
                    dp[i][j] = dp[i][j - 1] + dp[i - 1][j];
                }
            }
            System.out.println(dp[n][m]);

        }
    }
}