updated vignere cipher

Author: mandliya

README.md

@@ -139,7 +139,7 @@ Include contains single header implementation of data structures and some algori
 | In Quantumland, there are n cities numbered from 1 to n. Here, c<sub>i</sub> denotes the i<sup>th</sup> city. There are n−1 roads in Quantumland. Here, c<sub>i</sub> and c<sub>i+1</sub> have a bidirectional road between them for each i < n.There is a rumor that Flatland is going to attack Quantumland, and the queen wants to keep her land safe. The road between c<sub>i</sub> and c<sub>i+1</sub> is safe if there is a guard in c<sub>i</sub> or c<sub>i+1</sub>. The queen has already placed a few guards in some of the cities, but she is not sure if they are enough to keep the roads safe. She wants to know the minimum number of new guards she needs to hire. See comments in solution for input/output details. | [save_quantamland.cpp](common_ds_algo_problems/save_quantumland.cpp)|
 | You are given an integer N. Find the digits in this number that exactly divide N (division that leaves 0 as remainder) and display their count. For N=24, there are 2 digits (2 & 4). Both of these digits exactly divide 24. So our answer is 2. See more details in header comment of the solution file. | [findDigits.cpp](common_ds_algo_problems/findDigits.cpp)|
 | Encrypt and then decrypts a text using Caeser Cipher. | [caeser_cipher.cpp](common_ds_algo_problems/caeser_cipher.cpp)|
-| Encrypt and then decrypts a text using Vigenère cipher. | [vigenère_cipher.cpp](common_ds_algo_problems/vigenère_cipher.cpp)|
+| Encrypt and then decrypts a text using Vigenère cipher. | [vigenere_cipher.cpp](common_ds_algo_problems/vigenere_cipher.cpp)|
 
 ### Math Problems
 | Problem | Solution |