443_String_Compression

Author: partho-maple

README.md

@@ -260,6 +260,7 @@ I have solved quite a number of problems from several topics. See the below tabl
 |44| **[791. Custom Sort String](https://tinyurl.com/yag8mcfd)** | [Python](https://tinyurl.com/wu6rdaw/791_Custom_Sort_String.py), [Swift](https://tinyurl.com/wuja3c4/791_Custom_Sort_String.swift) | --- | Medium | Loved this problem |
 |45| **[157. Read N Characters Given Read4](https://tinyurl.com/y5g49nqt)** | [Python](https://tinyurl.com/wu6rdaw/157_Read_N_Characte_Given_Read4.py), [Swift](https://tinyurl.com/wuja3c4/157_Read_N_Characte_Given_Read4.swift) | --- | Easy (Not So!) | Loved this problem |
 |46| **[722. Remove Comments](https://tinyurl.com/y288v3lv)** | [Python](https://tinyurl.com/wu6rdaw/722_Remove_Comments.py), [Swift](https://tinyurl.com/wuja3c4/722_Remove_Comments.swift) | [Art 1](https://tinyurl.com/y56j4p76) | Medium |  |
+|47| **[443. String Compression](https://tinyurl.com/ybll48vn)** | [Python](https://tinyurl.com/wu6rdaw/443_String_Compression.py), [Swift](https://tinyurl.com/wuja3c4/443_String_Compression.swift) | [Art 1](https://tinyurl.com/y5knbkcd) | Medium |  |
 
 
 </p>

leetcode.com/swift/DS_ALGO_PRAC.playground/Sources/swift/443_String_Compression.swift

@@ -0,0 +1,26 @@
+import Foundation
+class Solution {
+    func compress(_ chars: inout [Character]) -> Int {
+        guard chars.count > 0 else {
+            return 0
+        }
+        
+        var (rPtr, wPtr) = (0, 0)
+        while rPtr < chars.count {
+            var (prevChar, frequency) = (chars[rPtr], 0)
+            while rPtr < chars.count && prevChar == chars[rPtr] {
+                frequency += 1
+                rPtr += 1
+            }
+            chars[wPtr] = prevChar
+            wPtr += 1
+            if frequency > 1 {
+                for num in Array(String(frequency)) {
+                    chars[wPtr] = num
+                    wPtr += 1
+                }
+            }
+        }
+        return wPtr
+    }
+}