#include<stdio.h>
long long int x[200005], y[200005];
long long int h[200005], l;
long long int comp_h(long long int a, long long int b)
{
	if (x[h[a]] > x[h[b]])
		return 1;
	else if (x[h[a]] < x[h[b]])
		return -1;
	else if (y[h[a]] > y[h[b]])
		return 1;
	else
		return -1;
}
void swap_h(long long int a, long long int b)
{
	long long int f = h[a];
	h[a] = h[b];
	h[b] = f;
	return;
}
void push(long long int ne)
{
	h[l] = ne;
	long long int p = l++;
	for (; p > 0; p = (p - 1) / 2)
		if (comp_h((p - 1) / 2, p) > 0)
			swap_h((p - 1) / 2, p);
	return;
}
long long int pop()
{
	swap_h(0, --l);
	long long int p = 0;
	for (;;)
	{
		if (2 * p + 2 < l)
		{
			if (comp_h(2 * p + 1, 2 * p + 2) > 0)
			{
				if (comp_h(p, 2 * p + 2) > 0)
					swap_h(p, 2 * p + 2);
				p = 2 * p + 2;
			}
			else
			{
				if (comp_h(p, 2 * p + 1) > 0)
					swap_h(p, 2 * p + 1);
				p = 2 * p + 1;
			}
		}
		else if (2 * p + 1 < l)
		{
			if (comp_h(p, 2 * p + 1) > 0)
				swap_h(p, 2 * p + 1);
			p = 2 * p + 1;
		}
		else
			break;
	}
	return h[l];
}
long long int c[200005];
int main()
{
	long long int n;
	scanf("%lld", &n);
	long long int i;
	for (i = 0; i < n; i++)
		scanf("%lld %lld", &x[i], &y[i]);
	l = 0;
	for (i = 0; i < n; i++)
		push(i);
	for (i = 0; i < n; i++)
		c[i] = pop();
	for (i = 0; i < n; i++)
		h[i] = x[i];
	for (i = 0; i < n; i++)
		x[i] = h[c[i]];
	for (i = 0; i < n; i++)
		h[i] = y[i];
	for (i = 0; i < n; i++)
		y[i] = h[c[i]];
	for (i = 0; i < n && x[i] == x[0]; i++);
	if (i > 2)
	{
		printf("No\n");
		return 0;
	}
	for (i = n - 1; i >= 0 && x[i] == x[n - 1]; i--);
	if (i < n - 3)
	{
		printf("No\n");
		return 0;
	}
	long long int cnt = 0;
	h[0] = 0;
	h[1] = 1;
	l = 1;
	for (i = 2; i < n; i++)
	{
		h[l + 1] = i;
		while ((y[h[l]] - y[h[l - 1]]) * (x[h[l + 1]] - x[h[l]]) <= (y[h[l + 1]] - y[h[l]]) * (x[h[l]] - x[h[l - 1]]))
		{
			h[l] = h[l + 1];
			l--;
			if (l == 0)
				break;
		}
		l++;
	}
	cnt += l;
	h[0] = 0;
	h[1] = 1;
	l = 1;
	for (i = 2; i < n; i++)
	{
		h[l + 1] = i;
		while ((y[h[l]] - y[h[l - 1]]) * (x[h[l + 1]] - x[h[l]]) >= (y[h[l + 1]] - y[h[l]]) * (x[h[l]] - x[h[l - 1]]))
		{
			h[l] = h[l + 1];
			l--;
			if (l == 0)
				break;
		}
		l++;
	}
	cnt += l;
	if (cnt < n)
		printf("No\n");
	else
		printf("Yes\n");
	return 0;
}