awk, 52 bytes

Result

AC

Duration

635ms

Code [DL]

t+=index($0,"T"){sub(/K /,1e99)}$0=substr($0,1,t-1)1

stdin

                                T                 
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
                                                  
  K                                               

stdout

                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
                                1
  9999999999999999673361688041161

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffdd307c360 /* 7 vars */) = 0
12    execve("/usr/bin/gawk", ["/usr/bin/gawk", "-f", "/volume/CODE"], 0x560592660068 /* 7 vars */ <unfinished ...>
11    execve("/bin/cat", ["cat", "-"], 0x5605906c2d58 /* 7 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 resumed> )            = 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 +++