标签:trre rev lag write sci min ascii substr strlen
攻防世界 web2 write up
minwen=‘a1zLbgQsCESEIqRLwuQAyMwLyq2L5VwBxqGA3RQAyumZ0tmMvSGM2ZwB4tws‘
#str_rot123()
minwen-1 = ‘n1mYotDfPRFRVdEYjhDNlZjYld2Y5IjOkdTN3EDNlhzM0gzZiFTZ2MjO4gjf‘
#strrev()
minwen-2 = ‘fjg4OjM2ZTFiZzg0MzhlNDE3NTdkOjI5Y2dlYjZlNDhjYEdVRFRPfDtoYm1n‘
#base64decode()
minwen-3 = ‘~88:36e1bg8438e41757d:29cgeb6e48c`GUDTO|;hbmg‘
for($_0=0;$_0<strlen($_o);$_0++){
$_c=substr($_o,$_0,1); #单个取字母
$__=ord($_c)+1; #将ascii码以此+1
$_c=chr($__); #将+1后的ascii码取为字符
$_=$_.$_c; #依顺序拼接
}
#所以只需要将+1改为-1
<?php
echo substr("Hello world",2,1)."<br>";
$_o ="~88:36e1bg8438e41757d:29cgeb6e48c`GUDTO|;hbmg";
$_="";
for($_0=0;$_0<strlen($_o);$_0++){
$_c=substr($_o,$_0,1);
$__=ord($_c)-1;
$_c=chr($__);
$_=$_.$_c;
}
echo $_;
?>
<?php
$flag="}77925d0af7327d30646c918bfda5d37b_FTCSN{:galf "."<br>";
echo strrev($flag);
?>
miwen="flag:{NSCTF_b73d5adfb819c64603d7237fa0d52977}"
标签:trre rev lag write sci min ascii substr strlen
原文地址:https://www.cnblogs.com/Zhu013/p/11533551.html