Python实现二分查找算法实例

#!/usr/bin/env python
import sys 
def search2(a,m):
  low = 0 
  high = len(a) - 1 
  while(low <= high):
    mid = (low + high)/2
    midval = a[mid]
    if midval < m:
      low = mid + 1 
    elif midval > m:
      high = mid - 1 
    else:
      print mid 
      return mid 
  print -1
  return -1
if __name__ == "__main__":
  a = [int(i) for i in list(sys.argv[1])]
  m = int(sys.argv[2])
  search2(a,m)