Improve the README file

Author: 0x61nas

README.md

@@ -8,6 +8,9 @@
 
 ## Problems
 - [Easy](./easy)
-   - [Roman to Integer](./easy/roman_to_integer/java/src/main/java/com/anas/leetcode/easy/RomanToInteger.java), [Problem in LeetCode](https://leetcode.com/problems/roman-to-integer/)
-   - [Longest Common Prefix](./easy/longest_common_prefix/java/src/main/java/com/anas/leetcode/easy/LongestCommonPrefix.java), [Problem in LeetCode](https://leetcode.com/problems/longest-common-prefix/)
-   - [Valid Parentheses](./easy/valid_parentheses/rust/valid_parentheses_checker/src/lib.rs), [Problem in LeetCode](https://leetcode.com/problems/valid-parentheses)
+   - [Roman to Integer](https://leetcode.com/problems/roman-to-integer/)
+      - [Java ☕](./easy/roman_to_integer/java/src/main/java/com/anas/leetcode/easy/RomanToInteger.java)
+   - [Longest Common Prefix](https://leetcode.com/problems/longest-common-prefix/)
+      - [Java ☕](./easy/longest_common_prefix/java/src/main/java/com/anas/leetcode/easy/LongestCommonPrefix.java)
+   - [Valid Parentheses](https://leetcode.com/problems/valid-parentheses)
+      - [Rust 🦀](./easy/valid_parentheses/rust/valid_parentheses_checker/src/lib.rs)