34 lines
1.1 KiB
Java
34 lines
1.1 KiB
Java
public class VigenereCipher {
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public static void main(String[] args) {
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String key = "VIGENERECIPHER";
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String ori = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";
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String enc = encrypt(ori, key);
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System.out.println(enc);
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System.out.println(decrypt(enc, key));
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}
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static String encrypt(String text, final String key) {
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String res = "";
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text = text.toUpperCase();
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for (int i = 0, j = 0; i < text.length(); i++) {
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char c = text.charAt(i);
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if (c < 'A' || c > 'Z') continue;
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res += (char)((c + key.charAt(j) - 2 * 'A') % 26 + 'A');
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j = ++j % key.length();
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}
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return res;
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}
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static String decrypt(String text, final String key) {
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String res = "";
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text = text.toUpperCase();
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for (int i = 0, j = 0; i < text.length(); i++) {
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char c = text.charAt(i);
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if (c < 'A' || c > 'Z') continue;
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res += (char)((c - key.charAt(j) + 26) % 26 + 'A');
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j = ++j % key.length();
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}
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return res;
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}
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}
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