题目地址：

https://www.lintcode.com/problem/is-alphanumeric/description

判断一个字符是否是数字或者字母。

代码如下：

public class Solution {
    /**
     * @param c: A character.
     * @return: The character is alphanumeric or not.
     */
    public boolean isAlphanumeric(char c) {
        // write your code here
        return Character.isDigit(c) || Character.isLetter(c);
    }
}

时空复杂度 O ( 1 ) O(1) O(1)。

标签：isLetter,return,23,character,Lintcode,Character,alphanumeric,public
来源： https://blog.csdn.net/qq_46105170/article/details/113430461