题目解析
输出 a 中 所有不属于 b 的字符
解题思路
可以暴力枚举 a 的字母是否在 b 中 出现过
也可以使用正则解决
代码
暴力
import java.io.*;
import java.math.*;
import java.util.*;
public class Main
{
public static void main(String[] args) throws IOException
{
char[] a = sc.readLine().toCharArray();
char[] b = sc.readLine().toCharArray();
Set<Character> s = new HashSet<Character>();
for (int i = 0; i < b.length; i++)
s.add(b[i]);
for (int i = 0; i < a.length; i++)
{
if (!s.contains(a[i]))
out.print(a[i]);
}
out.flush();
out.close();
}
static BufferedReader sc = new BufferedReader(new InputStreamReader(System.in));
static PrintWriter out = new PrintWriter(System.out);
}
正则
import java.io.*;
import java.math.*;
import java.util.*;
public class Main
{
public static void main(String[] args) throws IOException
{
String a = sc.readLine();
String b = sc.readLine();
out.println(a.replaceAll("[" + b + "]", ""));
out.flush();
out.close();
}
static BufferedReader sc = new BufferedReader(new InputStreamReader(System.in));
static PrintWriter out = new PrintWriter(System.out);
}