二分法猜数字

二分法

arr = range(10000000)
start = 0
end = len(arr)-1
res = 776575
count = 0
print arr.index(res)
while True:
    count = count+1
    mid = (start+end)/2
    if arr[mid]>res:
        end = mid
    elif arr[mid]<res:
        start = mid
    else:
        print mid
        break

print count