int flag=0;

    void binarysearch(int x, int a[], int m, int n)
    {
        int middle=(m+n)/2;
        if(a[middle]==x)
        {
            printf("%d has been found at postion %d!n", x, middle+1);
            flag=1;
        }
        else
        if(x > a[middle])
            binarysearch(x, a, middle, n);
        else
        if(x < a[middle])
            binarysearch(x, a, m, middle);
    }

    main()
    {
        int i, size, x;
        int a[100];
        printf("Enter the size of the list : ");
        scanf("%d", &size);
        printf("Enter the list items in ascending order : n");
        for (i=0; i<size; i++)
        scanf("%d", &a[i]);
        printf("Enter the element to be found : ");
        scanf("%d", &x);
        binarysearch(x, a, 0, size-1);
        if(flag != 1)
        printf("%d has not been found in the list!", x);
    }

if(m == n)
{
    if(a[n] == x) { printf("foundn"); }

    return;
}

int binarysearch(int x, int a[], int m, int n)
{
    int middle=(m+n)/2;
    if(a[middle]==x)
    {
        printf("%d has been found at postion %d!n", x, middle+1);
        return middle;
    }
    else
    if(x > a[middle])
        return binarysearch(x, a, middle, n);
    else
    if(x < a[middle])
        return binarysearch(x, a, m, middle);

   //if it is not found in the whole array
   return -1;


}

void binarysearch(int x, int a[], int m, int n)
    {
        int middle=(m+n)/2;
        if(n == m && x != a[middle])
        {
            printf("%d is not in the array", x);
            return;
        }
//...

void binarysearch(int x, int a[], int m, int n)
    {
        int middle=(m+n)/2;
        if(n == m && x != a[middle])
        {
            printf("%d is not in the array", x);
        }
        else
        if(a[middle]==x)
//...