不用加减乘除做加法

/****************************************************************
题目：写一个函数，求两个整数之和，要求在函数体内不得使用+、-、*、/
四则运算符号。
****************************************************************/
//对数字做运算，除了四则运算，就只剩下位运算
#include <stdio.h>

int Add(int num1, int num2)
{
    int sum, carry;
    do
    {
        sum = num1 ^ num2;
        carry = (num1 & num2) << 1;

        num1 = sum;
        num2 = carry;
    }
    while(num2 != 0);

    return num1;
}

// ====================测试代码====================
void Test(int num1, int num2, int expected)
{
    int result = Add(num1, num2);
    if(result == expected)
        printf("%d + %d is %d. Passed\n", num1, num2, result);
    else
        printf("%d + %d is %d. Failed\n", num1, num2, result);
}

int main()
{
    Test(1, 2, 3);
    Test(111, 899, 1010);

    Test(-1, 2, 1);
    Test(1, -2, -1);

    Test(3, 0, 3);
    Test(0, -4, -4);

    Test(-2, -8, -10);
}