编程题

另类加法

public static int addAB(int A, int B) {
    
    
        // write code here
        if (A == 0) {
    
    
            return B;
        }
        if (B == 0) {
    
    
            return A;
        }
        while (B != 0) {
    
    
            int sum = A ^ B;
            int carray = (A & B) << 1;
            A = sum;
            B = carray;
        }
        return A;
    }

走方格的方案数

import java.util.Scanner;

public class Main {
    
    

    public static void main(String[] args) {
    
    
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        System.out.println(func(n, m));
    }

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