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+---
+字符串相关
+---
+
+[05. 替换空格](https://leetcode-cn.com/problems/ti-huan-kong-ge-lcof/)
+
+```java
+class Solution {
+
+    public String replaceSpace(String s) {
+        StringBuilder builder = new StringBuilder();
+        int i = 0;
+        while (i < s.length()) {
+            char c = s.charAt(i);
+            if (c == ' ') {
+                builder.append("%20");
+            } else {
+                builder.append(c);
+            }
+            i++;
+        }
+        return builder.toString();
+    }
+}
+```
+