Hope I'm posting this in the correct forum..

[MikeM82]

Ok... student here... so I'm not looking for an answer... nearly some guidance... Sorry if I get the posting of it incorrect I'm just trying to find some help. And now my code blocker isn't working... so I can't exactly remember what the error code was but it has something to do with the string array. When I was running it, it seemed to try and change my key from a string to a character... sorry I can't get it exactly. I will try and fix my code blocker and post something else.

#include <iostream>
#include <string>
using namespace std;


template<typename T>
T binarySearch( const T list[], T key, int arraySize)
{
    int low = 0;
    int high = arraySize - 1;

    while (high >= low)
    {
        int mid = (low + high) / 2;
        if (key < list[mid])
            high = mid -1;
        else if (key == list[mid])
            return mid;
        else
            low = mid + 1;
    }
    return -1;
}

int main()
{

    int list1[] = {1,8, 15, 25, 33, 100, 200};
    cout << "The location of the number you are searching for is  " << binarySearch( list1, 15, 7) +1 << " on the list." << endl;

    double list2[] = {.125, 1.5, 9.8, 25.68, 98.44};
    cout << "The location of the number you are searching for is  " << binarySearch( list2, 98.44, 5) +1 << " on the list." << endl;

    char list3[] = {'A', 'B', 'D', 'H', 'L', 'M', 'R', 'S', 'T'};
    cout << "The location of the letter you are searching for is  " << binarySearch( list3, 'M', 9) +1 << " on the list." << endl;

    string list4[] = {"So", "Im", "getting", "hungry"};
    cout << "The location of the word you are searching for is  " << binarySearch( list4, "hungry", 4) +1 << " on the list." << endl;

    return 0;
}

[coder777]

Change line 38: "hungry" -> string("hungry"). It needs to be the same type. Or you define a second template parameter.

Line 7: The return type needs to be int.

[MikeM82]

The change to line 38 does not work. And on line 7, I am using template type so I don't want to be specific with that code.

[AbstractionAnon]

The change to line 38 worked for me. The implicit type of "hungry" is const char *, not string so it does not match the template. Note that fixing line 38 without fixing line 7 won't work.

And on line 7, I am using template type so I don't want to be specific with that code.

coder777 is correct. The return the of the function should be int, not T. Line 18 - You are returning the index (mid) which is an int, not an element of type T.

[MikeM82]

Ok I changed it and it works. But I have a question... why does it work for the other three and not the string. If you comment out the string it works fine. What is different about strings?

[AbstractionAnon]

The other three are all built-in types (int, double, char). The template recognizes those with no issue.

The problem arises as I stated in my previous post, because "hungry" in implicitly type const char *, not string.