solve problem String Compression

Author: P-ppc

README.md

@@ -181,6 +181,7 @@ All solutions will be accepted!
 |28|[Implement Strstr](https://leetcode-cn.com/problems/implement-strstr/description/)|[java/py/js](./algorithms/ImplementStrstr)|Easy|
 |459|[Repeated Substring Pattern](https://leetcode-cn.com/problems/repeated-substring-pattern/description/)|[java/py/js](./algorithms/RepeatedSubstringPattern)|Easy|
 |581|[Shortest Unsorted Continuous Subarray](https://leetcode-cn.com/problems/shortest-unsorted-continuous-subarray/description/)|[java/py/js](./algorithms/ShortestUnsortedContinuousSubarray)|Easy|
+|443|[String Compression](https://leetcode-cn.com/problems/string-compression/description/)|[java/py/js](./algorithms/StringCompression)|Easy|
 
 # Database
 |#|Title|Solution|Difficulty|

algorithms/StringCompression/README.md

@@ -0,0 +1,2 @@
+# String Compression
+This problem is easy to solve

algorithms/StringCompression/Solution.java

@@ -0,0 +1,43 @@
+class Solution {
+    public int compress(char[] chars) {
+        Character ch = null;
+        int count = 0,
+            length = 0;
+
+        for (char c : chars) {
+            if (ch == null) {
+                count = 1;
+                ch = c;
+            } else if (ch == c) {
+                count++;
+            } else if (ch != c) {
+                chars[length] = ch;
+                length++;
+
+                if (count > 1) {
+                    String countStr = String.valueOf(count);
+                    for (int j = 0; j < countStr.length(); j++) {
+                        chars[length] = countStr.charAt(j);
+                        length++;
+                    }
+                }
+
+                count = 1;
+                ch = c;
+            }
+        }
+
+        chars[length] = ch;
+        length++;
+
+        if (count > 1) {
+            String countStr = String.valueOf(count);
+            for (int j = 0; j < countStr.length(); j++) {
+                chars[length] = countStr.charAt(j);
+                length++;
+            }
+        }
+
+        return length;
+    }
+}

algorithms/StringCompression/solution.js

@@ -0,0 +1,45 @@
+/**
+ * @param {character[]} chars
+ * @return {number}
+ */
+var compress = function(chars) {
+    let char = null,
+        count = 0,
+        length = 0
+    
+    chars.forEach(c => {
+        if (char === null) {
+            count = 1
+            char = c
+        } else if (char === c) {
+            count++
+        } else if (char !== c) {
+            chars[length] = char
+            length++
+            
+            if (count > 1) {
+                let countStr = String(count)
+                for (let j = 0; j < countStr.length; j++) {
+                    chars[length] = countStr[j]
+                    length++
+                }
+            }
+            
+            count = 1
+            char = c
+        }
+    })
+    
+    chars[length] = char
+    length++
+
+    if (count > 1) {
+        let countStr = String(count)
+        for (let j = 0; j < countStr.length; j++) {
+            chars[length] = countStr[j]
+            length++
+        }
+    }
+    
+    return length
+};

algorithms/StringCompression/solution.py

@@ -0,0 +1,41 @@
+class Solution(object):
+    def compress(self, chars):
+        """
+        :type chars: List[str]
+        :rtype: int
+        """
+        char = None
+        count = 0
+        length = 0
+        
+        for c in chars:
+            if char == None:
+                count = 1
+                char = c
+            elif char == c:
+                count += 1
+            elif char != c:
+                chars[length] = char
+                length += 1
+                
+                if count > 1:
+                    count_str = str(count)
+                    for c in count_str:
+                        chars[length] = c
+                        length += 1
+                    
+                count = 1
+                char = c
+            
+        chars[length] = char
+        length += 1
+
+        if count > 1:
+            count_str = str(count)
+            for c in count_str:
+                chars[length] = c
+                length += 1
+        
+        return length
+                
+