Add C++ solution: 420. Strong Password Checker

C++/420-strong-password-checker.cpp

@@ -0,0 +1,64 @@
+// 420-strong-password-checker.cpp
+// Problem: https://leetcode.com/problems/strong-password-checker/
+//
+
+class Solution {
+public:
+    int strongPasswordChecker(string password) {
+        int x = password.size();
+        bool lower = false;
+        bool upper = false;
+        bool digit = false;
+
+        for(char i:password){
+            if(islower(i)){
+                lower = true;
+            }
+            if (isupper(i)){
+                upper = true;
+            }
+            if(isdigit(i)){
+                digit = true;
+            }
+        }
+
+        int miss = !lower + !upper + !digit;
+        int change = 0;
+        int one = 0;
+        int two = 0;
+
+        for (int i =2;i<x;i++){
+            if (password[i]==password[i-1] && password[i-1]==password[i-2]){
+                int j = i;
+                while (j < x && password[j]== password[i-2]){
+                    j++;
+                }
+                int len = j -(i-2);
+                change +=len/3;
+                if(len % 3 == 0){
+                    one++;
+                }
+                else if(len %3 == 1){
+                    two++;
+                }
+                i = j - 1;
+            }
+        }
+
+        if (x<6){ //CASE 1: TOO SHORT
+            return max(miss,6-x);
+        }
+
+        else if(x <=20){ //CASE 2: IDEAL RANGE
+            return max(miss,change);
+        }
+
+        else{ //REST, CASE 3: TOO LONG
+            int del = x -20;
+            change = change - min(del,one);
+            change = change - min(max(0,del-one), two *2)/2;
+            change = change - max(0,del-one-two*2)/3;
+            return del + max(miss, change);
+        }
+    }
+};

README.md

@@ -476,6 +476,7 @@ DISCLAIMER: This above mentioned resources have affiliate links, which means if
 
 | Name                                                                                                                                                                                               | Country        | Programming Language | Where to find you<br><sup>(add all links to your profiles eg on Hackerrank, Codechef, LeetCode...)</sup>                                                                                                                    |
 | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------- | -------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| [Genji J](https://github.com/anya-minamoto) <br> <img src="https://github.com/anya-minamoto.png" width="100" height="100">                                                                         | Indonesia      | C++                  | [GitHub](https://github.com/anya-minamoto) <br> [LeetCode](https://leetcode.com/u/anya-minamoto/) |
 | [Gourav R](https://github.com/GouravRusiya30/) <br> <img src="https://github.com/GouravRusiya30.png" width="100" height="100">                                                                     | India          | Java                 | [codedecks](https://www.youtube.com/c/codedecks/) <br> [Hackerrank](https://www.hackerrank.com/gouravrusiya786) <br> [LeetCode](https://leetcode.com/rusiya/)                                                               |
 | [Dima Vishnevetsky](https://github.com/dimshik100) <br> <img src="https://github.com/dimshik100.png" width="100" height="100">                                                                     | Israel         | JavaScript           | [Twitter](https://twitter.com/dimshik100) <br> [Facebook](https://www.facebook.com/dimshik)                                                                                                                                 |
 | [Anuj Sharma](https://github.com/Optider/) <br> <img src="https://github.com/Optider.png" width="100" height="100">                                                                                | India          | Python               | [Github](https://github.com/Optider)                                                                                                                                                                                        |