feat: add solutions to lcof2 problem: No.014 (doocs#724)

Author: CuteNineCats

lcof2/剑指 Offer II 014. 字符串中的变位词/README.md

@@ -142,6 +142,57 @@ func check(window []int) bool {
 }
 ```
 
+### **C++**
+
+```cpp
+class Solution {
+public:
+    bool checkInclusion(string s1, string s2) {
+
+        int len1 = s1.size();
+        int len2 = s2.size();
+
+        if (len2 < len1) {
+            return false;
+        }
+
+        int count[30] = {0};
+
+        for (int i = 0; i < len1; ++i) {
+            ++count[s1[i] - 'a'];
+            --count[s2[i] - 'a'];
+        }
+
+        int l = 0;
+        int r = len1 - 1;
+
+        while (r < len2) {
+
+            bool flag = true;
+
+            for (int i : count) {
+                if (i != 0) {
+                    flag = false;
+                }
+            }
+
+            if (flag) {
+                return true;
+            }
+
+            if (r + 1 >= len2) {
+                break;
+            }
+            
+            ++count[s2[l++] - 'a'];
+            --count[s2[++r] - 'a'];
+        }
+
+        return false;
+    }
+};
+```
+
 ### **...**
 
 ```

lcof2/剑指 Offer II 014. 字符串中的变位词/Solution.cpp

@@ -0,0 +1,46 @@
+class Solution {
+public:
+    bool checkInclusion(string s1, string s2) {
+
+        int len1 = s1.size();
+        int len2 = s2.size();
+
+        if (len2 < len1) {
+            return false;
+        }
+
+        int count[30] = {0};
+
+        for (int i = 0; i < len1; ++i) {
+            ++count[s1[i] - 'a'];
+            --count[s2[i] - 'a'];
+        }
+
+        int l = 0;
+        int r = len1 - 1;
+
+        while (r < len2) {
+
+            bool flag = true;
+
+            for (int i : count) {
+                if (i != 0) {
+                    flag = false;
+                }
+            }
+
+            if (flag) {
+                return true;
+            }
+
+            if (r + 1 >= len2) {
+                break;
+            }
+            
+            ++count[s2[l++] - 'a'];
+            --count[s2[++r] - 'a'];
+        }
+
+        return false;
+    }
+};