代码清单2-22
double MinDifference(double arr[], int n)
{
     if(n < 2)
     {
          return 0;
     }
     // Sort array arr[]
     Sort(arr, arr + n);

     double fMinDiff = arr[1] - arr[0];
     for(int i = 2; i < n; ++i)
     {
          double tmp = arr[i] - arr[i - 1];
          if(fMinDiff > tmp)
          {
               fMinDiff = tmp;
          }
     }
     return fMinDiff; 
}