Help! with binary search

Code:

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#include<iostream>#include<cstdlib>
#include<ctime>


void selectionSort(int[], int);
int binarySearch(const int[], int, int);




int main() {
    const int SIZE = 10;
    const int MAX = 100;
    int Array[SIZE] = { 0 };
    time_t t;
    srand((unsigned)time(&t));
    int search, results;


    for (int i = 0; i < SIZE; i++)
    {
        Array[i] = (rand() % MAX) + 1;
       
    }
    std::cout << std::endl;
   
    std::cout << "Array is " << std::endl;
    for (int i = 0; i < SIZE; i++)
    {
        std::cout << Array[i];
    }


    std::cout << "Sorted Array is " << std::endl;
    selectionSort(Array, SIZE);
    {
        for (int j = 0; j < SIZE; j++)
            std::cout << Array[j] << std::endl;       
    }


    std::cout << "What is your number " << std::endl;
    std::cin >> search;


    results = binarySearch(Array, SIZE, search);


    if (results == -1)
        std::cout << "No" << std::endl;
    else
    {
        std::cout << "Yes" << std::endl;
    }


    system("PAUSE");
    return 0;
}


void selectionSort(int array[], int size)
{
    int temp, i, j;
    for (i = 0; i < size; i++)
    {
        j = i;
        while (j > 0 && (array[j - 1] > array[j]))
        {
            temp = array[j];
            array[j] = array[j - 1];
            array[j - 1] = temp;
            j--;
        }
    }
}


int binarySearch(const int array[], int size, int value)
{
    int first = 0,
        last = size - 1,
        middle,
        position = -1;
    bool found = false;
   
    while (!found && first <= last)
    {
        middle = (first + last) / 2;
        if (array[middle] == value)
        {
            found = true;
            position = middle;
        }
        else if (array[middle] > value)
            last - middle - 1;
        else first = middle + 1;
    }


    return position;
}

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When I run this code I get my selection sort but I don't get the return of my binary search

Maybe you forgot an assignment?

Code:

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$ g++ -Wall -Wextra foo.cpp
foo.cpp: In function ‘int binarySearch(const int*, int, int)’:
foo.cpp:97:27: warning: statement has no effect [-Wunused-value]
            last - middle - 1;
                          ^

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Are you saying I need a pointer to my function?

How did you come up with that?

Read the error message.

"no effect" means you may as well have written

Code:

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        else if (array[middle] > value)
            ; // do nothing
        else first = middle + 1;

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Let me spell it out.
Write
last = middle - 1;