题目：不使用+,-,*,/做加法运算
^ 异或，不同为1
& 与，全1才1
<<左移,相当于乘2
public class Main65
{public static void main(String[] args){Scanner sc = new Scanner(System.in);int a = sc.nextInt();int b = sc.nextInt();System.out.println(getSum(a, b));}private static int getSum(int a, int b){int sum = (a ^ b);int carry = (a & b) << 1;if (carry != 0)sum = getSum(sum,carry );return sum;}
}