1. Regular expression to detect IP address
((2 [0-4] \d | 25[0-5] | [01]?\d\d?) \.){3}(2 [0-4] \d | 25[0-5] | [01]?\d\d?)
2 [0-4] \d: The first character is 2, the second character is 0-4
1. Regular expression to detect IP address
((2 [0-4] \d | 25[0-5] | [01]?\d\d?) \.){3}(2 [0-4] \d | 25[0-5] | [01]?\d\d?)
2 [0-4] \d: The first character is 2, the second character is 0-4