描述
Validate if a given string is numeric.
Some examples:
"0" => true
" 0.1 " => true
"abc" => false
"1 a" => false
"2e10" => true
Note: It is intended for the problem statement to be ambiguous. You should gather all requirements
up front before implementing one.
分析
细节实现题。
本题的功能与标准库中的 strtod() 功能类似
有效数字，用正则
代码
1 public class vaildNumber { 2 3 public static void main(String[] args) { 4 // TODO Auto-generated method stub 5 // String s="2e10"; 6 String s="1.5e10"; 7 System.out.println(vaildNumber(s)); 8 } 9 private static boolean vaildNumber(String s) { 10 if(s.length()==0) return false; 11 // "0" => true 12 // " 0.1 " => true 13 // "abc" => false 14 // "1 a" => false 15 // "2e10" => true 16 String regex="\\d+(\\.\\d+)?(e\\d+)?" ; 17 return s.matches(regex); 18 } 19 }