#include
#include
#include
using namespace std;
int input[1000000];
int main()
{
int n;
while (scanf("%d",&n)!=-1)
{
for (int i = 0; i < n; i++)
{
int w, l;
scanf("%d %d", &w, &l);
input[i] = w - l;
input[i + n] = input[i];
}
int cc = 0, ans = 0, sum = 0;
int j = n * 2;
for (int i = 0; i < j; i++)
{
sum += input[i];
if (sum >= 0)
cc++;
else
{
ans = max(cc, ans);
cc = 0;
sum = 0;
}
}
ans = max(cc, ans);
ans = min(ans, n);
printf("%d\n", ans);
}
return 0;
}