powershell, 31 bytes

Result

WA

Duration

1630ms

Code [DL]

$input -replace ".(.) ?$1","$1"

stdin

692 898
996 557
911 115
799 696
129 556
336 667
571 837
176 166
889 887
263 339
455 557
233 698
835 532
533 344
355 659
337 334
238 185
935 591
811 121
866 977
352 527
341 419
211 892
871 755
736 349
837 736
578 827
355 443
853 851
833 225
387 379
596 154

stdout

8
7
5
6
6
7
7
6
7
9
7
8
2
4
9
4
5
1
1
7
7
9
2
5
9
6
7
3
1
5
9
4

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffe0139a500 /* 6 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x562d153d5c10 /* 6 vars */) = 0
12    execve("/usr/bin/pwsh", ["/usr/bin/pwsh", "/volume/CODE"], 0x562d153d5c28 /* 6 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} ---
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} ---
31    +++ exited with 0 +++
30    +++ exited with 0 +++
32    +++ exited with 0 +++
29    +++ exited with 0 +++
28    +++ exited with 0 +++
27    +++ exited with 0 +++
26    +++ exited with 0 +++
25    +++ exited with 0 +++
24    +++ exited with 0 +++
23    +++ exited with 0 +++
22    +++ exited with 0 +++
21    +++ exited with 0 +++
20    +++ exited with 0 +++
19    +++ exited with 0 +++
18    +++ exited with 0 +++
17    +++ exited with 0 +++
14    +++ exited with 0 +++
13    +++ 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=34, si_stime=17} ---
10    +++ exited with 0 +++