Given two strings, find the length of the longest common substring.
The first line of input contains a positive integer t (t <= 100), which indicates the number of test cases. For each case, there are two strings in a line (length of the string <= 1000).
case 1: length of the string <= 30
case 2: length of the string <= 100
case 3: length of the string <= 1000
case 4: length of the string == 1000
Output the length of the longest common substring.