xslt, 291 bytes

Result

AC

Duration

4274ms

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$i in tokenize(input,'\n')return if(substring($i,2,1)=substring($i,3,1))then substring($i,3,1)else substring($i,5,1))"/></template></stylesheet>

stdin

911 891
956 537
484 338
622 242
451 119
413 115
189 891
458 588
511 113
577 476
298 382
455 117
977 732
182 281
811 765
311 117
539 987
283 573
252 563
397 382
223 336
861 163
379 334
354 758
676 964
244 113
355 155
822 193
783 347
221 521
727 227
164 726

stdout

15321185173572119553313794523527

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffe4078cd20 /* 7 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x55c3c191dd00 /* 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"], 0x55c3c20f0090 /* 7 vars */) = 0
12    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:preprocess.xsl", "-s:preprocess.xsl", "-o:/tmp/input.xml"], 0x7f486fb02f80 /* 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=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 +++
21    +++ exited with 0 +++
18    +++ exited with 0 +++
22    +++ exited with 0 +++
16    +++ exited with 0 +++
15    +++ exited with 0 +++
19    +++ exited with 0 +++
20    +++ 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=155, si_stime=31} ---
25    execve("/usr/bin/realpath", ["realpath", "/volume/CODE"], 0x55c3c191dd18 /* 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"], 0x55c3c191dd38 /* 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"], 0x55c3c20f0078 /* 7 vars */) = 0
27    execve("/usr/bin/java", ["java", "-jar", "saxon9he.jar", "-xsl:/tmp/code.xsl", "-s:/tmp/input.xml", "-o:/tmp/output"], 0x7f52747fdf60 /* 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 +++
39    +++ exited with 0 +++
37    +++ exited with 0 +++
36    +++ exited with 0 +++
35    +++ exited with 0 +++
34    +++ exited with 0 +++
33    +++ exited with 0 +++
31    +++ exited with 0 +++
30    +++ 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=169, si_stime=33} ---
40    execve("/bin/cat", ["cat", "/tmp/output"], 0x55c3c191dc98 /* 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"], 0x55c3c20f0068 /* 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 +++