Merge pull request neetcode-gh#1465 from sarangbg/main

Create: 438-find-all-anagrams-in-a-string.cs

Author: Ahmad-A0

csharp/438-Find-All-Anagrams-In-A-String.cs

@@ -0,0 +1,78 @@
+public class Solution
+{
+
+    public IList<int> FindAnagrams(string s, string p)
+    {
+        List<int> res = new List<int>();
+
+        int pSize = p.Length;
+        int sSize = s.Length;
+
+        if (pSize > sSize)
+        {
+            return res;
+        }
+
+        Dictionary<char, int> pHash = new Dictionary<char, int>();
+        Dictionary<char, int> sHash = new Dictionary<char, int>();
+
+        foreach (char c in p)
+        {
+            int tmp;
+            pHash.TryGetValue(c, out tmp);
+            pHash[c] = tmp + 1;
+        }
+
+        for (int x = 0; x < pSize; x++)
+        {
+            char c = s[x];
+            int tmp;
+            sHash.TryGetValue(c, out tmp);
+            sHash[c] = tmp + 1;
+        }
+
+        if (compareDict(pHash, sHash))
+        {
+            res.Add(0);
+        }
+
+        int i = 1;
+        int j = i + pSize - 1;
+
+        while (j < sSize)
+        {
+            sHash[s[i - 1]]--;
+
+            int tmp;
+            sHash.TryGetValue(s[j], out tmp);
+            sHash[s[j]] = tmp + 1;
+
+            if (compareDict(pHash, sHash))
+            {
+                res.Add(i);
+            }
+
+            i++;
+            j++;
+        }
+
+        return res;
+    }
+
+    public bool compareDict(Dictionary<char, int> d1, Dictionary<char, int> d2)
+    {
+        foreach (var i in d1)
+        {
+            if (d2.ContainsKey(i.Key) && i.Value == d2[i.Key])
+            {
+                continue;
+            }
+            else
+            {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}