regex - Java regular expression for negative numbers?

Question

I have this pattern:

Pattern.compile("T([0-9]*)");

which works fine for positive numbers but I need it to also do negative numbers for instance "T-1T3T44" should work. Or maybe use space instead of 'T' so it should work for strings like this:"-1 2 3 2 -1 6 2". Sorry I haven't really used regular expressions before.So any suggestions? Thanks.

Answer 1

Pattern.compile("T(-{0,1}(?!0)\d+)"); 

Please note the usage of negative look-ahead (?!0) to exclude -0 number and numbers that start with 0.