Who can explain to me in what sense of this problem???

I got AC with this program

time 0.015
memory 236 КБ

#include <stdio.h>

#define MAXN 10000

int A[MAXN], ans[MAXN + 1];
int N, L1, i;
int i2, l, cnt, tmp;

int BinarySearch(int x)
{
    int p, q, i, L;

    p = 0;   /* Left border of the search  */
    q = N-1; /* Right border of the search */
    L = 0;   /* Comparison counter         */

    while (p <= q)
    {
        i = (p + q) / 2;
        ++L;
        if (A[i] == x)
        {
//            printf("Found item i = %d in L = %d comparisons", i, L);
            return L;
        }
        if (x < A[i])
            q = i - 1;
        else
            p = i + 1;
    }

    return 0;
}


int main()
{
    scanf("%d %d", &i, &L1);

    for (i2 = 0; i2 <= MAXN; i2++)
    {
        A[i2] = i2;
        N = i2;
        if (BinarySearch(i) == L1)
        {
            ans[i2] = 1;
        }
    }



    cnt = 0;
    tmp = 0;
    for (i2 = 0; i2 <= MAXN; i2++)
    {
        if (ans[i2] == 0) tmp = 0;
        else
        {
            if (tmp == 0) cnt++;
            tmp = 1;
        }
    }
    printf("%d\n", cnt);

    tmp = 0;
    l = -1;
    for (i2 = 0; i2 <= MAXN; i2++)
    {

        if (ans[i2] == 0)
        {
            if (l != -1) printf("%d %d\n", l, i2-1);
            l = -1;
            tmp = 0;
        }
        else
        {
            if (tmp == 0) l = i2;
            tmp = 1;
        }
    }

    if (l != -1) printf("%d %d", l, MAXN);

    return 0;
}

Simple simulation :) with O(n * log(n)). (n in not greater 10000)