xslt, 292 bytes

Result

AC

Duration

4462ms

Code [DL]

<stylesheet version="1.0" xmlns="http://www.w3.org/1999/XSL/Transform"><output method="text"/><template match="/"><value-of select="string-join(for$i in tokenize(input,'\n')return let$a:=substring($i,3,1)return if(substring($i,2,1)=$a)then$a else substring($i,5,1))"/></template></stylesheet>

stdin

586 662
733 326
644 463
852 851
779 772
784 646
155 955
818 189
998 447
497 773
332 132
847 668
866 661
325 257
624 146
566 368
859 545
811 628
688 556
449 711
299 991
244 663
925 223
695 595
936 316
697 749
646 724
849 946
376 353
477 432
778 962
194 472

stdout

63487651471662165187942537793794

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffe42eb8050 /* 7 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x55c269dbfd00 /* 7 vars */) = 0
11    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=11, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
12    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:preprocess.xsl", "-s:preprocess.xsl", "-o:/tmp/input.xml"], 0x55c26a523090 /* 7 vars */) = 0
12    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:preprocess.xsl", "-s:preprocess.xsl", "-o:/tmp/input.xml"], 0x7fcd17a91f80 /* 8 vars */) = 0
12    --- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TKILL, si_pid=12, si_uid=0} ---
12    --- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TKILL, si_pid=12, si_uid=0} ---
13    --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=NULL} ---
13    --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0xc} ---
13    --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x14} ---
13    --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x14} ---
23    +++ exited with 0 +++
17    +++ exited with 0 +++
14    +++ exited with 0 +++
13    +++ exited with 0 +++
24    +++ exited with 0 +++
22    +++ exited with 0 +++
15    +++ exited with 0 +++
16    +++ exited with 0 +++
18    +++ exited with 0 +++
21    +++ exited with 0 +++
20    +++ exited with 0 +++
19    +++ exited with 0 +++
12    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=12, si_uid=0, si_status=0, si_utime=174, si_stime=23} ---
25    execve("/usr/bin/realpath", ["realpath", "/volume/CODE"], 0x55c269dbfd18 /* 7 vars */) = 0
25    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=25, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
26    execve("/bin/ln", ["ln", "-sf", "/volume/CODE", "/tmp/code.xsl"], 0x55c269dbfd38 /* 7 vars */) = 0
26    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=26, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
27    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:/tmp/code.xsl", "-s:/tmp/input.xml", "-o:/tmp/output"], 0x55c26a523078 /* 7 vars */) = 0
27    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:/tmp/code.xsl", "-s:/tmp/input.xml", "-o:/tmp/output"], 0x7f701f537f60 /* 8 vars */) = 0
27    --- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TKILL, si_pid=27, si_uid=0} ---
27    --- SIGRT_2 {si_signo=SIGRT_2, si_code=SI_TKILL, si_pid=27, si_uid=0} ---
28    --- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=NULL} ---
38    +++ exited with 0 +++
32    +++ exited with 0 +++
29    +++ exited with 0 +++
28    +++ exited with 0 +++
36    +++ exited with 0 +++
37    +++ exited with 0 +++
31    +++ exited with 0 +++
30    +++ exited with 0 +++
39    +++ exited with 0 +++
35    +++ exited with 0 +++
33    +++ exited with 0 +++
34    +++ exited with 0 +++
27    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=27, si_uid=0, si_status=0, si_utime=168, si_stime=35} ---
40    execve("/bin/cat", ["cat", "/tmp/output"], 0x55c269dbfc98 /* 7 vars */) = 0
40    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=40, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
41    execve("/bin/rm", ["rm", "/tmp/input", "/tmp/input.xml", "/tmp/code.xsl", "/tmp/output"], 0x55c26a523068 /* 7 vars */) = 0
41    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=41, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
10    +++ exited with 0 +++