转载 若干面试题目

1、字符串
“

A@B@C@D

”，以
@
字符拆分

返回数组



String[] strs =
"A@B@C@D"
.split(
"@"
);

String[] strs = "A@B@C@D".split("@");

2
、字符串
String s=
”
SDsBEaA
”
,
要求最后生成
s=
”
AaBDESs
”



import
java.util.*;

public

class
Test{

public

static

void
main(String[] args) {

//System.out.println(countBits(-1));

System.out.println(sortString("SDsBEaA"
));

}

//排序方法 public static String sortString(String str){

Character[] characters=new
Character[str.length()];

char
[] strchars=str.toCharArray();

int
count=
0
;

for
(
char
c:strchars){

characters[count++]=c;

}

//采用匿名类的方式重写比较方法类

Arrays.sort(characters,new
Comparator<Character>(){

public

int
compare(Character c1,Character c2){

if
(c1.equals(c2))
return

0
;

if
(Character.toLowerCase(c1)==Character.toLowerCase(c2)){

return
c1-c2;

}else
{

return
Character.toLowerCase(c1)-Character.toLowerCase(c2);

}

}

public

boolean
equals(Object o){

return

true
;

}

});

count=0
;

for
(Character c: characters){

strchars[count++]=c;

}

return

new
String(strchars);

}

}

import java.util.*;
public class Test{
public static void main(String[] args) {
//System.out.println(countBits(-1));
System.out.println(sortString("SDsBEaA"));
}
//排序方法    public static String sortString(String str){
Character[] characters=new Character[str.length()];
char[] strchars=str.toCharArray();
int count=0;
for(char c:strchars){
characters[count++]=c;
}
//采用匿名类的方式重写比较方法类
Arrays.sort(characters,new Comparator<Character>(){
public int compare(Character c1,Character c2){
if(c1.equals(c2))return 0;
if(Character.toLowerCase(c1)==Character.toLowerCase(c2)){
return c1-c2;
}else{
return Character.toLowerCase(c1)-Character.toLowerCase(c2);
}
}
public boolean equals(Object o){
return true;
}
});
count=0;
for(Character c: characters){
strchars[count++]=c;
}
return new String(strchars);
}
}

3、用HTML做出如下效果：



view plain
copy to clipboard
print
?

<
table

width
=
"30%"

border
=
"0"

bgcolor
=
"#000000"
>

<
tr
>

<
td

colspan
=
"4"

bgcolor
=
"#FFFFFF"
>
1
</
td
>

</
tr
>

<
tr
>

<
td

rowspan
=
"4"

bgcolor
=
"#FFFFFF"
>
2
</
td
>

<
td

colspan
=
"3"

bgcolor
=
"#FFFFFF"
>
3
</
td
>

</
tr
>

<
tr
>

<
td

rowspan
=
"3"

bgcolor
=
"#FFFFFF"
>
4
</
td
>

<
td

colspan
=
"2"

bgcolor
=
"#FFFFFF"
>
5
</
td
>

</
tr
>

<
tr
>

<
td

rowspan
=
"2"

bgcolor
=
"#FFFFFF"
>
6
</
td
>

<
td

bgcolor
=
"#FFFFFF"
>
7
</
td
>

</
tr
>

<
tr
>

<
td

bgcolor
=
"#FFFFFF"
>
8
</
td
>

</
tr
>

</
table
>

<table width="30%" border="0" bgcolor="#000000">
<tr>
<td colspan="4" bgcolor="#FFFFFF">1</td>
</tr>
<tr>
<td rowspan="4" bgcolor="#FFFFFF">2</td>
<td colspan="3" bgcolor="#FFFFFF">3</td>
</tr>
<tr>
<td rowspan="3" bgcolor="#FFFFFF">4</td>
<td colspan="2" bgcolor="#FFFFFF">5</td>
</tr>
<tr>
<td rowspan="2" bgcolor="#FFFFFF">6</td>
<td bgcolor="#FFFFFF">7</td>
</tr>
<tr>
<td bgcolor="#FFFFFF">8</td>
</tr>
</table>

4、给你一个字符串，包含了空格等标点符号，要你计算出出现次数最多的字母和该字母出现的次数。



public

static

void
main(String[] args) {

Map<String,Long> charTimesMap = new
HashMap<String,Long>();

String str = "hello wolrd wlllkcdfdfdfdfdfdfdfdsfhksadfl,,,,,,,,,,,,,,,,,,,,,s?sdfls fjs"
;

str = str.replaceAll("[^a-zA-Z]"
,
""
);

//以字符为key，以出现次数为value存入Map中

for
(
char
each : str.toCharArray()) {

String charStr = String.valueOf(each);

if
(charTimesMap.containsKey(charStr)) {

Long num = charTimesMap.get(charStr).longValue() + 1
;

charTimesMap.put(charStr, num);

} else
{

charTimesMap.put(charStr, 1L);

}

}

String maxAppearChar = null
;

Long maxAppearTimes = 0L;

//遍历map，entrySet()方法取得map集合

for
(Map.Entry<String, Long> charAppear : charTimesMap.entrySet()) {

if
(charAppear.getValue() > maxAppearTimes) {

maxAppearChar = charAppear.getKey();

maxAppearTimes = charAppear.getValue();

}

}

System.out.println("出现最多的字母："
+maxAppearChar);

System.out.println("出现次数:"
+maxAppearTimes);

}