259201 Lab13.2

#include "iostream"
using namespace std;

int main()
{
    bool found = false;
    const int arraySize = 13;
    int a[arraySize] = {1,5,15,19,25,27,29,31,33,45,55,88,100};
    int key,low = 0,middle,high = (arraySize - 1),counter = 1;

    cout <<"Enter search key: ";
    cin >> key;
    while(low <= high)
    {
        cout<<"Pass#"<<counter<<": ";
        for (int i = 0; i < arraySize; ++i)
        {
            if(i == low && low != high)
            {
                cout<<"["<<a[i];
            }
            else if (i == high && low != high)
            {
                cout<<" "<<a[i]<<"]";
            }
            else if (i == low && low == high)
            {
                cout<<"["<<a[i]<<"]";
            }
            else
            {
                cout<<" "<<a[i];
            }
        }

        middle = (low+high)/2;

        if(key == a[middle])
        {
            found = true;
            cout <<endl<<"Found element "<<key<<" at index "<<middle<<endl;
            break;
        }
        else if (key < a[middle])
        {
            high = middle - 1;          // search low end of array
        }
        else
        {
            low = middle + 1;           // search high end of array
        }

        counter++;
        cout<<endl;
    }

    if(!found)
    {
        cout <<"Could not find element "<<key<<" in array a"<<endl;

    }

    return 0;
}