Description

In the intensive care unit, a patient's blood pressure is measured every hour. The blood pressure is considered normal if the systolic pressure is between $90$ and $140$ (inclusive) and the diastolic pressure is between $60$ and $90$ (inclusive). Given the blood pressure measurements of a patient over several hours, calculate the longest duration of consecutive hours during which the patient's blood pressure remained normal.

Input Format

The first line contains an integer $n$ ($n<100$).
The next $n$ lines each contain two positive integers, representing the systolic and diastolic pressures of a measurement (both within the range [$1,200$]), separated by a space.

Output Format

Output a single line containing the longest duration of consecutive hours during which the blood pressure remained normal.

Sample

4
100 80
90 50
120 60
140 90

2