Yuki's Blog

隊名: 從缺 rk.13

我只解出一題，我超廢，隊友超給力!

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先用 die 看一下用啥寫的，很好，C#

用 dnspy 看一下寫了啥東西，這邊看起來就怪怪的，有藏一些東西在裡面

把這段 code 直接塞上去 online compiler，直接出 flag

code(整理過的):

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using System;
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using System.Text;
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public class HelloWorld
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{
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    public static void Main(string[] args)
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    {
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        string text3 = "1565023222387235312162663";
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    string text4 = string.Format("{0}", (long.Parse(text3.Substring(0, 5)) ^ 56L) + 65681531L) + string.Format("{0}", (long.Parse(text3.Substring(5, 4)) ^ 8L) + 83121454L) + string.Format("{0}", (long.Parse(text3.Substring(9, 8)) ^ 56L) + 65681531L) + string.Format("{0}", (long.Parse(text3.Substring(17, 8)) ^ 8L) + 83121454L);
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    int[] array = new int[]
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    {
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      2,
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      2,
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      2,
26 collapsed lines
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      2,
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      2,
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      3,
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      2,
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      2,
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      2,
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      2,
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      2,
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      2,
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      2,
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      2,
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      3
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    };
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    StringBuilder stringBuilder = new StringBuilder();
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    int num = 0;
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    foreach (int num2 in array)
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    {
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      string s = text4.Substring(num, num2);
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      int num3 = int.Parse(s);
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      char value = (char)num3;
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      stringBuilder.Append(value);
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      num += num2;
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    }
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        Console.WriteLine (stringBuilder.ToString());
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    }
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}

flag: AEGIS{N0_5WE4T}

2024 AEGIS 神盾盃 Writeup

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