fish, 25 bytes

Result

AC

Duration

1085ms

Code [DL]

<v:$;!?:<*d2*d7
 >i)n$1-^

stdin

ABCDEfGHIJKLMNOPQRSTUVWxYZ

stdout

11111011111111111111111011

stderr

strace

11    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffde42754e0 /* 7 vars */) = 0
12    execve("/bin/cat", ["cat", "-"], 0x55e7eca0fd68 /* 7 vars */) = 0
13    execve("/usr/bin/python3", ["/usr/bin/python3", "/root/fish.py", "/volume/CODE"], 0x55e7ed87c028 /* 7 vars */ <unfinished ...>
12    +++ exited with 0 +++
13    <... execve resumed>)             = 0
11    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=12, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
13    +++ exited with 0 +++
11    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=13, si_uid=0, si_status=0, si_utime=6, si_stime=2} ---
11    +++ exited with 0 +++