使用Javascript實現Amicable numbers

問題描述：

Let d(n) be defined as the sum of proper divisors of n (numbers less than n which divide evenly into n).
If d(a) = b and d(b) = a, where a  b, then a and b are an amicable pair and each of a and b are called amicable numbers.

For example, the proper divisors of 220 are 1, 2, 4, 5, 10, 11, 20, 22, 44, 55 and 110; therefore d(220) = 284. The proper divisors of 284 are 1, 2, 4, 71 and 142; so d(284) = 220.

Evaluate the sum of all the amicable numbers under 10000.

實現：

(function(){        var factor = function (n){  var arr = new Array();  for(var i = 1;i < n; i++)  {  if(n%i == 0 && arr.indexOf(i) == -1)  arr.push(i);  }  return arr;  }        var sumArr = function(arr){  var sum = 0 ;        for(var i = 0 ; i < arr.length; i++)  sum += arr[i];        return sum ;  }              for(var i = 2;i< 10000; i++)  {  var r1 = sumArr(factor(i));  var r2 = sumArr(factor(r1));        if(i == r2 && i != r1)  console.log("num1 : " + i + ", num2 : " + r1);  }        })();

查看本欄目更多精彩內容：http://www.bianceng.cnhttp://www.bianceng.cn/webkf/script/