v-vim, 26 bytes

Result

WA

Duration

809ms

Code [DL]

:%s/.*\(.\)\(\1\| \).*/\1/

stdin

423 886
944 553
327 778
927 759
245 227
224 729
689 982
243 133
114 416
582 826
699 998
547 443
633 234
397 963
288 869
533 327
179 796
626 683
178 977
588 584
636 374
995 995
922 966
245 749
711 778
825 552
789 351
169 744
695 455
612 672
133 331
955 341

stdout

8
5
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7
2
4
9
3
4
2
9
4
3
7
8
3
9
6
7
8
6
9
6
5
7
5
9
4
5
2
3
5

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffcbbc1dd30 /* 9 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x55ff973f7d00 /* 9 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("/root/V/v", ["/root/V/v", "/volume/CODE", "-f", "/tmp/input"], 0x55ff973f7d38 /* 9 vars */) = 0
14    execve("/usr/bin/readlink", ["readlink", "-e", "--", "/root/V/v"], 0x558208c5dc20 /* 10 vars */) = 0
14    +++ exited with 0 +++
13    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=14, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
13    execve("/usr/bin/dirname", ["dirname", "--", "/root/V/v"], 0x558208c5d3c0 /* 10 vars */) = 0
13    +++ exited with 0 +++
12    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=13, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
15    execve("/usr/bin/vim", ["vim", "-Nnes", "/tmp/input", "-u", "/root/V/vim/init.vim", "-i", "NONE", "-c", "call Execute_Program('/volume/CO"..., "-c", "%p", "-c", "q!"], 0x558208c5cbc0 /* 11 vars */) = 0
16    execve("/usr/bin/head", ["head", "-c", "-1"], 0x558208c5cbc0 /* 11 vars */) = 0
15    +++ exited with 0 +++
16    +++ exited with 0 +++
12    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15, si_uid=0, si_status=0, si_utime=0, si_stime=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=0, si_stime=0} ---
10    +++ exited with 0 +++