haskell, 70 bytes

Result

AC

Duration

1096ms

Code [DL]

m s|s!!1==s!!2=s!!2|True=s!!4
main=getContents>>=mapM(putChar.m).lines

stdin

829 223
675 663
922 217
966 694
659 291
394 961
445 153
696 636
786 683
533 225
396 698
148 884
476 741
678 678
793 228
677 552
743 437
266 322
788 881
551 793
377 594
688 182
255 414
987 516
443 321
199 799
974 742
249 118
688 887
454 442
717 816
325 223

stdout

26262916636876274687785539718482

stderr

strace

14    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffcad6fd8e0 /* 7 vars */) = 0
15    execve("/bin/cat", ["cat", "-"], 0x55d2891b2d30 /* 7 vars */ <unfinished ...>
16    execve("/usr/bin/runghc", ["/usr/bin/runghc", "/volume/CODE"], 0x55d2891b2d40 /* 7 vars */ <unfinished ...>
15    <... execve resumed>)             = 0
16    <... execve resumed>)             = 0
15    +++ exited with 0 +++
14    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
16    execve("/usr/lib/ghc-8.8.3/bin/runghc", ["/usr/lib/ghc-8.8.3/bin/runghc", "-f", "/usr/bin/ghc-8.8.3", "/volume/CODE"], 0x560108cbf168 /* 7 vars */) = 0
16    execve("/usr/bin/ghc-8.8.3", ["/usr/bin/ghc-8.8.3", "-ignore-dot-ghci", "-x", "hs", "-e", ":set prog \"/volume/CODE\"", "-e", ":main []", "/volume/CODE"], 0x7ffe347e7a60 /* 7 vars */) = 0
16    execve("/usr/lib/ghc-8.8.3/bin/ghc", ["/usr/lib/ghc-8.8.3/bin/ghc", "-B/usr/lib/ghc-8.8.3", "-ignore-dot-ghci", "-x", "hs", "-e", ":set prog \"/volume/CODE\"", "-e", ":main []", "/volume/CODE"], 0x55cd051c9200 /* 7 vars */) = 0
21    execve("/bin/gcc", ["gcc", "-DTABLES_NEXT_TO_CODE", "-B/usr/lib/ghc-8.8.3/integer-gmp"..., "--print-file-name", "libgmp.so"], 0x7ffc4df2eb90 /* 7 vars */) = -1 ENOENT (No such file or directory)
21    execve("/usr/local/sbin/gcc", ["gcc", "-DTABLES_NEXT_TO_CODE", "-B/usr/lib/ghc-8.8.3/integer-gmp"..., "--print-file-name", "libgmp.so"], 0x7ffc4df2eb90 /* 7 vars */) = -1 ENOENT (No such file or directory)
21    execve("/usr/local/bin/gcc", ["gcc", "-DTABLES_NEXT_TO_CODE", "-B/usr/lib/ghc-8.8.3/integer-gmp"..., "--print-file-name", "libgmp.so"], 0x7ffc4df2eb90 /* 7 vars */) = -1 ENOENT (No such file or directory)
21    execve("/usr/sbin/gcc", ["gcc", "-DTABLES_NEXT_TO_CODE", "-B/usr/lib/ghc-8.8.3/integer-gmp"..., "--print-file-name", "libgmp.so"], 0x7ffc4df2eb90 /* 7 vars */) = -1 ENOENT (No such file or directory)
21    execve("/usr/bin/gcc", ["gcc", "-DTABLES_NEXT_TO_CODE", "-B/usr/lib/ghc-8.8.3/integer-gmp"..., "--print-file-name", "libgmp.so"], 0x7ffc4df2eb90 /* 7 vars */) = 0
21    +++ exited with 0 +++
18    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=21, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
18    +++ exited with 0 +++
19    +++ exited with 0 +++
22    +++ exited with 0 +++
20    +++ exited with 0 +++
17    +++ exited with 0 +++
16    +++ exited with 0 +++
14    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=16, si_uid=0, si_status=0, si_utime=19, si_stime=7} ---
14    +++ exited with 0 +++