catf1ag CTF

class

import java.util.ArrayList;
import java.util.Scanner;

//
// Decompiled by Procyon v0.5.36
//

public class Reverse
{
    public static void main(final String[] array) {
        final Scanner scanner = new Scanner(System.in);
        System.out.println("Please input the flag \uff1a");
        final String next = scanner.next();
        System.out.println("Your input is \uff1a");
        System.out.println(next);
        Encrypt(next.toCharArray());
    }

    public static void Encrypt(final char[] array) {
        final ArrayList<Integer> list = new ArrayList<Integer>();
        for (int i = 0; i < array.length; ++i) {
            list.add(array[i] + '@' ^ 0x20);
        }
        final int[] array2 = { 131, 129, 148, 134, 140, 129, 135, 155, 138, 129, 150, 129, 191, 133, 129, 147, 153, 191, 133, 129, 147, 153, 157 };
        final ArrayList<Integer> o = new ArrayList<Integer>();
        for (int j = 0; j < array2.length; ++j) {
            o.add(array2[j]);
        }
        System.out.println("Result:");
        if (list.equals(o)) {
            System.out.println("Congratulations\uff01");
        }
        else {
            System.err.println("Error\uff01");
        }
    }
}

简单

data=[ 131, 129, 148, 134, 140, 129, 135, 155, 138, 129, 150, 129, 191,
       133, 129, 147, 153, 191, 133, 129, 147, 153, 157 ]
for i in range(len(data)):
       data[i]^=0x20
       data[i]-=ord('@')
print(''.join(chr(x)for x in data))