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Replaced String with StringBuilder so multiple String Objects don't get created (#2238)

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Ankit Sharma 2021-06-05 20:31:32 +05:30 committed by GitHub
parent 0fd737e555
commit e67212138c
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GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 11 additions and 10 deletions
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21
ciphers/Vigenere.java
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@ -4,50 +4,51 @@ package ciphers;
* A Java implementation of Vigenere Cipher.
*
* @author straiffix
* @author beingmartinbmc
*/
public class Vigenere {
public static String encrypt(final String message, final String key) {
String result = "";
StringBuilder result = new StringBuilder();
for (int i = 0, j = 0; i < message.length(); i++) {
char c = message.charAt(i);
if (Character.isLetter(c)) {
if (Character.isUpperCase(c)) {
result += (char) ((c + key.toUpperCase().charAt(j) - 2 * 'A') % 26 + 'A');
result.append((char) ((c + key.toUpperCase().charAt(j) - 2 * 'A') % 26 + 'A'));
} else {
result += (char) ((c + key.toLowerCase().charAt(j) - 2 * 'a') % 26 + 'a');
result.append((char) ((c + key.toLowerCase().charAt(j) - 2 * 'a') % 26 + 'a'));
}
} else {
result += c;
result.append(c);
}
j = ++j % key.length();
}
return result;
return result.toString();
}
public static String decrypt(final String message, final String key) {
String result = "";
StringBuilder result = new StringBuilder();
for (int i = 0, j = 0; i < message.length(); i++) {
char c = message.charAt(i);
if (Character.isLetter(c)) {
if (Character.isUpperCase(c)) {
result += ((char) ('Z' - (25 - (c - key.toUpperCase().charAt(j))) % 26));
result.append((char) ('Z' - (25 - (c - key.toUpperCase().charAt(j))) % 26));
} else {
result += ((char) ('z' - (25 - (c - key.toLowerCase().charAt(j))) % 26));
result.append((char) ('z' - (25 - (c - key.toLowerCase().charAt(j))) % 26));
}
} else {
result += c;
result.append(c);
}
j = ++j % key.length();
}
return result;
return result.toString();
}
public static void main(String[] args) {