output ==> elif mid_number<query: TypeError: '<' not supported between instances-CodePudding

cards= [20,19,18,17,16,15,13, 11, 10, 7, 4, 3, 1, 0], 
query=1
    
def checker(cards,query,mid,lo,hi):
    mid_number = cards[mid]
    print('mid',mid,', mid_number: ',mid_number,' lo ',lo,' hi ',hi)
    
    if mid_number == query:
        if mid-1>=0 and cards[mid-1] == query:
            return 'left'
        else:
            return 'found'
    elif mid_number<query:
        return 'left'
    else:
        return 'right'        

def locate_card(cards, query):
    lo, hi = 0, len(cards) - 1
    
    while (lo   hi) // 2 != query:
        mid = (lo   hi) // 2
        result = checker(cards,query,mid,lo,hi)
        
        if result == 'found':
            return mid
        elif result == 'left':
            hi = mid - 1  
        elif result ==  'right':
            lo = mid   1
    
print(locate_card(cards, query))

output

    elif mid_number<query:
TypeError: '<' not supported between instances of 'list' and 'int'

CodePudding user response：

In you code you write: (pay attention to , in the end of line)

cards= [20,19,18,17,16,15,13, 11, 10, 7, 4, 3, 1, 0],

this code convert cards to the tuple and when you write cards[0] this return :

>>> cards[0]
[20,19,18,17,16,15,13, 11, 10, 7, 4, 3, 1, 0]

to mid_number and when you check mid_number with int you check list with int and got an error.

Then you need to change this line like below:

>>> cards= [20,19,18,17,16,15,13, 11, 10, 7, 4, 3, 1, 0]
>>> cards[0]
20

CodePudding user response：

Try comparing the values from a for loop.

for i in cards:
    if i == mid:
       if i < query:
           return 'left'
    {...}