golang, 99 bytes

Result

AC

Duration

1635ms

Code [DL]

package main
import."fmt"
func main(){for{a,b:=0,0;Scan(&a,&b);if 0/a+b%110<9{a=b/10};Print(a%10)}}

stdin

373 451
387 779
392 292
551 996
822 227
764 668
547 443
755 529
477 662
372 725
871 128
722 779
744 348
688 298
546 247
974 226
983 651
655 158
146 491
367 566
758 484
311 169
721 149
459 953
916 662
213 135
849 191
911 115
257 647
866 454
312 189
486 585

stdout

37292645621248623567811963917626

stderr

panic: runtime error: integer divide by zero

goroutine 1 [running]:
main.main()
	/tmp/code.go:3 +0x1f1

strace

10    execve("/bin/sh", ["/bin/sh", "/root/script", "/volume/CODE"], 0x7fffa4bc1370 /* 7 vars */) = 0
11    execve("/usr/bin/realpath", ["realpath", "/volume/CODE"], 0x55b6cc7b1d18 /* 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("/bin/ln", ["ln", "-sf", "/volume/CODE", "/tmp/code.go"], 0x55b6cc7b1d38 /* 7 vars */) = 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} ---
13    execve("/usr/bin/go", ["/usr/bin/go", "build", "-o", "/tmp/code", "/tmp/code.go"], 0x55b6cd1c2028 /* 7 vars */) = 0
20    execve("/usr/lib/go/pkg/tool/linux_amd64/compile", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-V=full"], 0xc00013e1a0 /* 25 vars */) = 0
21    execve("/usr/lib/go/pkg/tool/linux_amd64/compile", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-V=full"], 0xc000143d40 /* 25 vars */) = 0
25    +++ exited with 0 +++
23    +++ exited with 0 +++
24    +++ exited with 0 +++
20    +++ exited with 0 +++
16    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=20, si_uid=0, si_status=0, si_utime=0, si_stime=1} ---
27    +++ exited with 0 +++
28    +++ exited with 0 +++
29    +++ exited with 0 +++
21    +++ exited with 0 +++
19    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=21, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
26    execve("/usr/lib/go/pkg/tool/linux_amd64/asm", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-V=full"], 0xc000143ee0 /* 25 vars */) = 0
30    execve("/usr/lib/go/pkg/tool/linux_amd64/asm", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-V=full"], 0xc00013e410 /* 25 vars */) = 0
33    +++ exited with 0 +++
32    +++ exited with 0 +++
31    +++ exited with 0 +++
26    +++ exited with 0 +++
19    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=26, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
34    ????( <unfinished ...>
35    +++ exited with 0 +++
34    +++ exited with 0 +++
36    +++ exited with 0 +++
30    +++ exited with 0 +++
16    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=30, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
38    execve("/usr/lib/go/pkg/tool/linux_amd64/compile", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-o", "/tmp/go-build365064514/b001/_pkg"..., "-trimpath", "/tmp/go-build365064514/b001=>", "-p", "main", "-complete", "-buildid", "Gfw6dZvnLtVyR98vltuj/Gfw6dZvnLtV"..., "-goversion", "go1.13.10", "-D", "_/tmp", "-importcfg", "/tmp/go-build365064514/b001/impo"..., "-pack", "-c=2", "/tmp/code.go"], 0xc000398410 /* 25 vars */) = 0
42    +++ exited with 0 +++
41    +++ exited with 0 +++
40    +++ exited with 0 +++
39    +++ exited with 0 +++
38    +++ exited with 0 +++
37    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=38, si_uid=0, si_status=0, si_utime=1, si_stime=0} ---
43    execve("/usr/lib/go/pkg/tool/linux_amd64/link", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-V=full"], 0xc000340340 /* 25 vars */) = 0
46    +++ exited with 0 +++
45    +++ exited with 0 +++
44    +++ exited with 0 +++
43    +++ exited with 0 +++
37    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=43, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
47    execve("/usr/lib/go/pkg/tool/linux_amd64/link", ["/usr/lib/go/pkg/tool/linux_amd64"..., "-o", "/tmp/go-build365064514/b001/exe/"..., "-importcfg", "/tmp/go-build365064514/b001/impo"..., "-buildmode=exe", "-buildid=DAggzhCmRqpsFQUd6wRD/Gf"..., "-extld=gcc", "/tmp/go-build365064514/b001/_pkg"...], 0xc000340820 /* 25 vars */) = 0
51    +++ exited with 0 +++
49    +++ exited with 0 +++
48    +++ exited with 0 +++
50    +++ exited with 0 +++
47    +++ exited with 0 +++
37    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=47, si_uid=0, si_status=0, si_utime=20, si_stime=5} ---
22    +++ exited with 0 +++
19    +++ exited with 0 +++
37    +++ exited with 0 +++
18    +++ exited with 0 +++
16    +++ exited with 0 +++
14    +++ exited with 0 +++
17    +++ exited with 0 +++
15    +++ exited with 0 +++
13    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=13, si_uid=0, si_status=0, si_utime=3, si_stime=16} ---
52    execve("/bin/cat", ["cat", "-"], 0x55b6cc7b1d08 /* 7 vars */) = 0
53    execve("/tmp/code", ["/tmp/code"], 0x55b6cc7b1cf0 /* 7 vars */) = 0
52    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=52, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
56    +++ exited with 2 +++
55    +++ exited with 2 +++
54    +++ exited with 2 +++
53    +++ exited with 2 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=53, si_uid=0, si_status=2, si_utime=0, si_stime=0} ---
57    execve("/bin/rm", ["rm", "/tmp/code.go", "/tmp/code"], 0x55b6cc7b1cf0 /* 7 vars */) = 0
57    +++ exited with 0 +++
10    --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=57, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
10    +++ exited with 0 +++