使用二分搜索的猜谜游戏

Question

I am trying to make a guessing game using binary search

here is my code:

import random

def guess():
a = 0
b = 100
c = random.randint(1,100)
count = 1

user = int(input("Guess a number from 1 to 100: "))
comp = int(input(f"\nIs ur number {c}\nIf its high write 0 \nIf its low write 2\nIf it is then write 1: "))

while comp != 1:
count += 1

if comp == 0:
  c = (a + c) // 2

elif comp == 2:
  c = (c + b) // 2

comp = int(input(f"\nIs ur number {c} \nif its high press 0 \nif its low press 2\nif its ur number press 1: "))

print(f"\nYour number was {user} and it took {count} turn to find ur number.")

guess()

The problem i am facing is with the binary search

for eg:

assuiming our guess number is  = 55

our random number genrated = 22

user will press 2 cause it low resulting a number = (22 + 100) // 2
                                                  = 61  
since 61 in higher than 55

# here lies the problem in the 2nd loop
user will press 1 cause its high resulting a number = (0 + 61) // 2
                                                    = 30

It finds the middle number from 0 to 61 which i dont want

What i want is it to find the middle number for 22 something like this:

(22 + 61) // 2 causing it to give us 41

then (41 + 61) // 2 causing it to print 51

then (51 + 61) // 2 causing it to print 56

then (56 + 51 ) // 2 causing it to print 53

then (53 + 56 ) // 2 causing it to print 54

then (54 + 56 ) // 2 causing it to print 55

55 which is our guess number

Answer 1

I made the following modifications to your function in order to narrow the interval of research as itprorh66 suggested. The code is the following:

def guess():
    a = 0
    b = 100
    c = random.randint(1,100)
    count = 1
    
    user = int(input("Guess a number from 1 to 100: "))
    comp = int(input(f"\nIs ur number {c}\nIf its high write 0 \nIf its low write 2\nIf it is then write 1: "))
    
    while comp != 1:
        count += 1
    
        if comp == 0:
            b=c
            c = (a + c) // 2
          
        
        elif comp == 2:
            a=c
            c = (c + b) // 2
        comp = int(input(f"\nIs ur number {c} \nif its high press 0 \nif its low press 2\nif its ur number press 1: "))

    print(f"\nYour number was {user} and it took {count} turn to find ur number.")