/**
      * 循環(huán)實現(xiàn)累加方法
      * @param value
      * @return
      */
     private static long cycle(long value) {
         long sum = 0;

         for (long i = 1,v = value; i <= v; i++) {
             sum += i;
         }
         return sum;
     }

/**
      * 高斯方法:<code>(n+1)*n/2</code><br>
      * you can read more from <a >Here</a>
      * @param value
      * @return
      */
     private static long gaosi(long value) {
         long sum = 0;
         sum = (value + 1) * value / 2;
         return sum;
     }

/**
  *
  */
 package com.b510.arithmetic;

 /**
  * 累加算法實現(xiàn)<br>
  *
  * @date 2013-4-16
  * @author hongten
  *
  */
 public class AddArithmetic {

     /**
      * 循環(huán)實現(xiàn)累加方法
      * @param value
      * @return
      */
     private static long cycle(long value) {
         long sum = 0;

         for (long i = 1,v = value; i <= v; i++) {
             sum += i;
         }
         return sum;
     }

     /**
      * 高斯方法:<code>(n+1)*n/2</code><br>
      * you can read more from <a >Here</a>
      * @param value
      * @return
      */
     private static long gaosi(long value) {
         long sum = 0;
         sum = (value + 1) * value / 2;
         return sum;
     }

     public static void main(String[] args) {
         //清理一下內(nèi)存，但不一定會執(zhí)行
         System.gc();
         // you should change value,then get the different results
         long value = 10000000;
         long sum = 0;
         long start = System.currentTimeMillis();
         sum = cycle(value);
         long end = System.currentTimeMillis();
         System.out.println("使用循環(huán)累加方法從[1]累加到["+value+"]用時 ： ["+(end - start) + "]ms,結(jié)果："+ sum);
         //清理一下內(nèi)存，但不一定會執(zhí)行
         System.gc();
         start = System.currentTimeMillis();
         sum = gaosi(value);
         end = System.currentTimeMillis();
         System.out.println("使用高斯方法從[1]累加到["+value+"]用時 ： ["+(end - start) + "]ms,結(jié)果："+ sum);

     }

 }

使用循環(huán)累加方法從[1]累加到[10000000]用時 ： [24]ms,結(jié)果：50000005000000
使用高斯方法從[1]累加到[10000000]用時 ： [0]ms,結(jié)果：50000005000000