Binary_Search

Simple Binary Search 

The my_binary function will find the value named key and check if the key value is in the array list or not.The function will return -1 if the key value is not in the array list else it will return the position of the element in the array list

int my_binary(int ara[], int lo, int hi, int key, int siz)

{

    if(hi>=lo)

    {

        int mid = lo + (hi-lo)/2;

        if(ara[mid]==key)

            return mid;

        if(key>ara[mid])

            return my_binary(ara,mid+1,hi,key,siz);

        else

            return my_binary(ara,lo,mid-1,key,siz);

    }

    return -1;      

}

int my_lower_binary(int ara[], int lo, int hi, int key, int siz)

{

    if(hi>=lo)

    {

        int mid = lo + (hi-lo)/2;

        if((mid==0 || key>ara[mid-1]) && ara[mid]==key)

            return mid;

        else if(key>ara[mid])

            return my_lower_binary(ara,mid+1,hi,key,siz);

        else

            return my_lower_binary(ara,lo,mid-1,key,siz);

    }

    return -1;

}

int my_upper_binary(int ara[], int lo, int hi, int key, int siz)

{

    if(hi>=lo)

    {

        int mid = lo + (hi-lo)/2;

        if((mid==siz-1 || key<ara[mid+1]) && ara[mid]==key)

            return mid;

        else if(key<ara[mid])

            return my_upper_binary(ara,lo,mid-1,key,siz);

        else

            return my_upper_binary(ara,mid+1,hi,key,siz);

    }

    return -1;

}