1 #include <cstdlib>
 2 #include <cstdio>
 3 #include <iostream>
 4 
 5 using namespace std;
 6 
 7 int main(int argc, char *argv[])
 8 {
 9     int n, a, b;
10     while (scanf("%d", &n)!=EOF)
11     {
12         int i, j, res[100000], max=0, count=0,flag=0, temp=0;
13         for (i=0; i<n; i++)
14         {
15             scanf("%d%d", &a, &b);
16             res[i] = a - b;
17             temp += res[i];
18             if (temp >= 0)
19                 count++;
20             else
21             {
22                 count = 0;
23                 temp = 0;
24             }     
25             if (count > max)
26                 max = count;
27         }
28         for(i=0;i<n;i++)
29         {
30             temp += res[i];
31             if (temp >= 0)
32                 count++;
33             else
34             {
35                 count = 0;
36                 temp = 0;
37             }     
38             if (count > max)
39                 max = count;
40         }
41         printf("%d\n", max>n?n:max);  
42     }
43     //  system("PAUSE");
44     return 0;
45 }