oh, 103 bytes

Result

AC

Duration

1142ms

Code [DL]

define a:""::split:readline
if(eq($a::get 1)($a::get 2)){
echo:$a::get 1
}else:echo:$a::get 4
source $0

stdin

339 936
496 931
338 335
192 658
377 171
855 886
362 223
944 338
344 443
174 472
374 468
564 642
593 236
734 471
667 626
131 779
828 256
388 885
379 886
334 137
199 271
518 689
133 436
717 171
877 461
344 423
646 352
527 198
422 262
978 676
357 773
494 997

stdout

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

stderr

boot.oh: 360: error/runtime: argument 1 (of 1) is invalid

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7fffd9f1b810 /* 7 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x56497e1b5048 /* 7 vars */) = 0
13    execve("/usr/bin/go", ["/usr/bin/go", "env", "GOPATH"], 0x56497e1b5078 /* 7 vars */ <unfinished ...>
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} ---
13    <... execve resumed>)             = 0
14    +++ exited with 0 +++
15    +++ exited with 0 +++
16    +++ exited with 0 +++
18    +++ exited with 0 +++
17    +++ exited with 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} ---
12    execve("/root/go/bin/oh", ["/root/go/bin/oh", "/volume/CODE"], 0x56497e1b5068 /* 7 vars */) = 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 +++
12    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=12, si_uid=0, si_status=0, si_utime=4, si_stime=7} ---
10    +++ exited with 0 +++