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:
判断字符串是否满足满足某些规则,应该想到正则表达式。
public class Solution { public boolean isNumber(String s) { if(s == null || s.trim().length()==0) return false; String regex = "[-+]?(\\d+\\.?|\\.\\d+)\\d*(e[-+]?\\d+)?"; if(s.trim().matches(regex)) return true; return false; } }