面试题05. 替换空格

冷不防 2023-07-18 04:46 17阅读 0赞

# 题目： #

[面试题05. 替换空格][05.]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p5eF9seQ_size_16_color_FFFFFF_t_70]

# 题解： #

## 1. 题解一：使用API ##

Java replace() 方法

## 2. 题解二：模拟过程 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p5eF9seQ_size_16_color_FFFFFF_t_70 1]

## 3. 题解三：使用StringBuilder ##

使用StringBuilder代替String

# 代码： #

## 1. 代码一：使用API ##

/** * 面试题05 */
    public class 面试题05 { 
    
        public static String replaceSpace(String s) { 
            String str = s.replace(" ", "%20");
            return str;
        }
    
        public static void main(String[] args) { 
            String s = "We are happy.";
            String res = replaceSpace(s);
            System.out.println(s);
            System.out.println(res);
        }
    }

## 2. 代码二：模拟过程 ##

/** * 面试题05 */
    public class 面试题05 { 
    
        public static String replaceSpace(String s) { 
            String res = new String();
            char c[] = s.toCharArray();
            for (int i = 0; i < c.length; i++) { 
                if (c[i] == ' ') { 
                    res += "%20";
                } else { 
                    res += c[i];
                }
            }
            return res;
        }
    
        public static void main(String[] args) { 
            String s = "We are happy.";
            String res = replaceSpace(s);
            System.out.println(s);
            System.out.println(res);
        }
    }

## 3. 代码三：使用StringBuilder ##

/** * 面试题05 */
    public class 面试题05 { 
    
        public static String replaceSpace(String s) { 
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < s.length(); i++) { 
                if (s.charAt(i) == ' ') { 
                    sb.append("%20");
                } else { 
                    sb.append(s.charAt(i));
                }
            }
            return sb.toString();
        }
    
        public static void main(String[] args) { 
            String s = "We are happy.";
            String res = replaceSpace(s);
            System.out.println(s);
            System.out.println(res);
        }
    }

# 参考： #

1.  [面试题05. 替换空格][05. 1]
2.  [面试题05. 替换空格 （极简，清晰图解）][05. _]
3.  [C++8行，双百][C_8]
4.  [Java replace() 方法][Java replace_]
5.  [Java split() 方法][Java split_]
6.  [String,StringBuffer与StringBuilder的区别??][String_StringBuffer_StringBuilder]
7.  [Java深究之String、StringBuffer、StringBuilder的区别][Java_String_StringBuffer_StringBuilder]

# 注： #

String、StringBuffer、StringBuilder的共同点：
    
    1.三者在java中都是用来处理字符串的
    
    2.三个类都被final修饰，因此都是不可继承的
    
    3.StringBuilder与StringBuffer有公共父类AbstractStringBuilder(抽象类)

String、StringBuffer、StringBuilder的区别：
    
    1. 基本区别:
    String的对象不可变，StringBuffer和StringBuilder的对象是可变的。
    
    2. 性能区别:
    在大部分情况下 StringBuilder > StringBuffer > String
    
    3. 安全区别:
    String、StringBuffer是线程安全的，StringBuilder是线程不安全的

[05.]: https://leetcode-cn.com/problems/ti-huan-kong-ge-lcof/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p5eF9seQ_size_16_color_FFFFFF_t_70]: /images/20230528/54fcf88897a44e17897479322f272b97.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p5eF9seQ_size_16_color_FFFFFF_t_70 1]: /images/20230528/e89fd3616bb44fd59e0d464ceb975637.png
[05. 1]: https://leetcode-cn.com/problems/ti-huan-kong-ge-lcof/solution/mian-shi-ti-05-ti-huan-kong-ge-by-leetcode-solutio/
[05. _]: https://leetcode-cn.com/problems/ti-huan-kong-ge-lcof/solution/mian-shi-ti-05-ti-huan-kong-ge-ji-jian-qing-xi-tu-/
[C_8]: https://leetcode-cn.com/problems/ti-huan-kong-ge-lcof/solution/c9xing-shuang-bai-by-fan-hua-man-zhi-tou/
[Java replace_]: https://www.runoob.com/java/java-string-replace.html
[Java split_]: https://www.runoob.com/java/java-string-split.html
[String_StringBuffer_StringBuilder]: https://blog.csdn.net/rmn190/article/details/1492013
[Java_String_StringBuffer_StringBuilder]: https://my.oschina.net/zss1993/blog/1838615