Binary search for strings python

I'm relatively new to python[3.3] and I'm just trying to do a binary search through a list of words, and cant figure out how to fix my operand types when it comes down to looping through the indices... I continue to get the TypeError. Cant figure out any way around it

def find[L, target]:
    start = 0
    end = len[L] - 1

    while start  target:
            end = midpoint - 1
        elif midpoint < target:
            start = midpoint + 1
        else:
            return midpoint

I'm calling the function as so:

L = ["Brian", "Meg", "Peter", "Joe", "Stewie", "Lois"]

find[L, "Joe"]

tdelaney

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asked Dec 17, 2015 at 5:28

7

Your logic seems fine, except for the input and the bug with incrementing and decrementing midpoint instead of middle.

def find[L, target]:
    start = 0
    end = len[L] - 1

    while start  target:
            end = middle - 1
        elif midpoint < target:
            start = middle + 1
        else:
            return midpoint

L = ["Brian", "Joe", "Lois", "Meg", "Peter", "Stewie"] # Needs to be sorted.

print find[L, "Peter"]

Bhargav Rao

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answered Dec 17, 2015 at 5:40

jianweichuahjianweichuah

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2

def find[L, target]:
    start = 0
    end = len[L] - 1
    while start  target:
            end = middle - 1
        elif midpoint < target:
            start = middle + 1
        else:
            return midpoint

    L = ["Brian", "Joe", "Lois", "Meg", "Peter", "Stewie"]
    L = sorted[L]
    print[find[L, "Lois"]]

As pointed out by others, use middle instead of midpoint

And to optimally use binary search, sort the list first

Vivek Sable

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answered Dec 17, 2015 at 5:44

Prashant YadavPrashant Yadav

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1

def binarySearchOnString[arr, x]:
        l = 0
        r = len[arr] - 1
        while [l 

Javascript
function binarySearch[arr,x]
{

  

    let l = 0, r = arr.length - 1;
        while [l  0]
                l = m + 1;
            else
                r = m - 1;
        }
        return -1;
}
let arr=["contribute", "geeks", "ide", "practice"];
let x = "ide";
let result = binarySearch[arr, x];
if [result == -1]
    document.write["Element not present
"];
else
    document.write["Element found at "
                   + "index " + result+"
"];
Output
Element found at index 2