Нахождение количества единиц в отсортированном бинарном масс

#include <iostream>
#include <string>
#include <cmath>
int* mas;
using namespace std;

int main()
{
	cout.flush();

	int n, h, check = 0;
	scanf("%d", &n);
	if (n <= 0)
	{
		printf("!");
		printf(" %d", 0);
		check = 1;
	}
	if (check == 0)
	{
		mas = new int[n+1];
		for (int i = 1; i <= n+1; i++)
		{
			mas[i] = -1;
		}
		int l, r, m, ans;
		l = 1;
		r = n;

		while (l - r < 0)
		{
			m = (l + r + 1) / 2;
			if (mas[m] >= 0)
				h = mas[m];
			else
			{
				printf("? %d\n", m);
				fflush(stdout);
				scanf("%d", &h);
				mas[m] = h;
			}
			mas[m] = h;
			if (h <= 0)
			{
				l = m;
			}
			else
			{
				r = m - 1;
			}
		}
		if (mas[l] != -1)
			h = mas[l];
		else
		{
			printf("? %d\n", l);
			fflush(stdout);
			scanf("%d", &h);
		}
		if (h == 0)
		{
			ans = n - l;
		}
		if (h == 1)
		{
			ans = n;
		}
		printf("!");
		printf(" %d", ans);
	}
}