算法：冒泡排序、一阶滤波

冒泡排序

/* 冒泡 */
void bubbleSort(int a[], int n)
{
  int i, j, tmp; 
  for(i =0 ; i< n-1; ++i)
  {
    for(j = 0; j < n-i-1; ++j)
    {
      if(a[j] > a[j+1])
      {
        tmp = a[j];
        a[j] = a[j+1];
        a[j+1] = tmp;
      }
    }
  }
}

/* 改良 */
void Bubble_1( int a[], int n)
{
  int i, j, tmp; 
  int pos = 0;
  
  i = n - 1;
  while(i > 0)
  {
    pos = 0;
    for(j = 0; j < i; j++)
    {
      if(a[j] > a[j+1])
      {
        pos = j; //记录交换的位置
 
        tmp = a[j];
        a[j] = a[j+1];
        a[j+1] = tmp;
      }
    }
    i= pos;
  }
}

一阶滤波

/* 一阶滤波 Y(n)=αX(n) + (1-α)Y(n-1) */
long lvbo_test(long NEW_DATA,unsigned char k)
{ 
 long result;                //声明一个变量作为滤波缓存
 if( NEW_DATA < OLD_DATA )
 {
    result = OLD_DATA - NEW_DATA;
    result *= k;
    result += 128;   //+128是为了四舍五入
    result /= 256;
    result =  OLD_DATA - result;
 }
 else if( NEW_DATA > OLD_DATA )
 {
    result = NEW_DATA - OLD_DATA;
    result *= k;
    result += 128;   //+128是为了四舍五入
    result /= 256;
    result =  OLD_DATA + result; 
 }
 else
 {
    result = OLD_DATA;
 }
 OLD_DATA = result;
 return  result; 
}