Problem Statement

Takahashi recorded his daily life for the last few days as a integer sequence of length ~2N~ , as follows:

• ~a_1, b_1, a_2, b_2, ... , a_N, b_N~

This means that, starting from a certain time ~T~ , he was:

• sleeping for exactly ~a_1~ seconds
• then awake for exactly ~b_1~ seconds
• then sleeping for exactly ~a_2~ seconds
• :
• then sleeping for exactly ~a_N~ seconds
• then awake for exactly ~b_N~ seconds

In this record, he waked up ~N~ times.

Takahashi is wondering how many times he waked up early during the recorded period.

Here, he is said to wake up early if he wakes up between ~4:00~ AM and ~7:00~ AM, inclusive.

If he wakes up more than once during this period, each of these awakenings is counted as waking up early.

Unfortunately, he forgot the time ~T~ .

Find the maximum possible number of times he waked up early during the recorded period.

For your information, a day consists of ~86400~ seconds, and the length of the period between ~4:00~ AM and ~7:00~ AM is ~10800~ seconds.

Constraints

• ~1 \leq N \leq 10^5~
• ~1 \leq a_i, b_i \leq 10^5~
• ~a_i~ and ~b_i~ are integers.

Input

The input is given from Standard Input in the following format:

~N~

~a_1~ ~b_1~

~a_2~ ~b_2~

~a_N~ ~b_N~

Output

Print the maximum possible number of times he waked up early during the recorded period.

Sample Input 1

3
28800 57600
28800 57600
57600 28800

Sample Output 1

2

Sample Input 2

10
28800 57600
4800 9600
6000 1200
600 600
300 600
5400 600
6000 5760
6760 2880
6000 12000
9000 600

Sample Output 2

5