lua, 132 bytes

Result

AC

Duration

947ms

Code [DL]

for i = 0, 31, 1 do
a,b = io.read("*n","*n")
if a%10 == (a%100 - a%10)/10
then io.write (a%10)
else io.write ((b-b%100)/100)
end
end

stdin

993 695
645 251
198 668
899 881
315 885
388 856
288 886
211 121
826 215
739 597
982 112
659 517
875 758
617 774
118 815
244 197
544 946
926 964
245 246
124 245
869 997
977 663
866 664
837 627
679 977
739 972
376 773
221 229
883 327
633 539
578 561
677 856

stdout

62698881251577844922976699723357

stderr

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7ffee2317110 /* 7 vars */) = 0
11    execve("/bin/cat", ["cat", "-"], 0x5608105d9d30 /* 7 vars */ <unfinished ...>
12    execve("/usr/bin/lua5.3", ["/usr/bin/lua5.3", "/volume/CODE"], 0x5608105d9d40 /* 7 vars */ <unfinished ...>
11    <... execve resumed>)             = 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 +++