如何在JavaScript中不使用减号的情况下减去两个数字？或使用For循环

Question

JavaScript未使用按位运算符??这是我的代码javascript代码

function subtract()
{
    var n1 = parseInt(document.getElementById('fvalue').value);
    var n2 = parseInt(document.getElementById('svalue').value);
    var x1, x2;

    while(n2 != 0)
    {
        var brw = (~n2)&n2;
        n1= n1^n2;
        n2 = brw<<1;
    }

    document.write("Result is : " + n1);
}

Answer 1

这是在javascript中添加和减去2个数字的简单示例：

console.log(add(2,4));
console.log(subtract(5,4));

function add( a, b)
{
   var x;
  x = a^b;

  while(a&b)
  {
    b = ((a&b)<<1);
    a = x;
    x = a^b;
    //b=(a^b);
  }

  return x;
}
function subtract( x,  y) 
{ 
    if (y == 0) 
        return x; 
    return subtract(x ^ y, (~x & y) << 1); 
}