Tetstack
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So okay that maths is this, which mathematically would work but idk
                                                                   DAT_00104020                                                                                    XREF[2]:               FUN_001014b0:001014c4(*), 
FUN_001014b0:001014d5(R)
00104020 04 00 00 00 undefined4 00000004h
DAT_00104024 XREF[1]: FUN_001014b0:001014d5(R)
00104024 4f 00 00 00 undefined4 0000004Fh
00104028 81 db 81h
00104029 00 ?? 00h
0010402a 00 ?? 00h
0010402b 00 ?? 00h
0010402c ab ?? ABh
0010402d 00 ?? 00h
0010402e 00 ?? 00h
0010402f 00 ?? 00h

But there are 2 XREF sooo wait ...
so still this only computes number from whatever string I typed
undefined8 FUN_001011f0(void) {
int iVar1;
ostream *poVar2;
long in_FS_OFFSET;
int local_7c;
undefined1 *local_78;
long local_70;
undefined1 local_68 [16];
string local_58 [40];
long local_30;

local_30 = *(long *)(in_FS_OFFSET + 0x28);
local_78 = local_68;
local_68[0] = 0;
local_70 = 0;
poVar2 = std::operator<<((ostream *)std::cout,"Enter a string of characters (no spaces): ");
FUN_00101430(poVar2);
std::operator>>((istream *)std::cin,(string *)&local_78);
if (5 < local_70 - 5U) {
std::operator<<((ostream *)std::cout,"Bro, what are you trying to do?");
FUN_00101430();
/* WARNING: Subroutine does not return */
exit(0);
}
poVar2 = std::operator<<((ostream *)std::cout,"Enter correct number (no spaces): ");
FUN_00101430(poVar2);
std::istream::operator>>((istream *)std::cin,&local_7c);
std::__cxx11::string::string(local_58,(string *)&local_78);
iVar1 = FUN_001014b0(local_58);
std::__cxx11::string::_M_dispose();
if (local_7c == iVar1) {
poVar2 = std::operator<<((ostream *)std::cout,"OMG! You did it! :3");
}
else {
poVar2 = std::operator<<((ostream *)std::cout,"Send help pls.");
}
FUN_00101430(poVar2);
std::__cxx11::string::_M_dispose();
if (local_30 == *(long *)(in_FS_OFFSET + 0x28)) {
return 0;
}
/* WARNING: Subroutine does not return */
__stack_chk_fail();
}

so which means I missed smthing here
so I finalized it to this code that's the logic I suppose if you enter any character longer than 5 it exits with that message and then the next one is the number you type must be equal to the checksum of your string..
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the check sum is this the comments for simplification ...
time to try it
so wait
ghidra did unsigned substraction so .... local_70 is the string length, the expression length_70 - 5U is unsigned
this underflows to a huge number, which is >5, so the real condition is local_70 <5
so wait
the range is 5 to 10
as 6 or 7, 8, 9, 10 -5 are in range and true on the 5 < (local_70 -5U)
Give me a bit of time I am done with a and to go for the rest ....
Had to use a calculator
So for the string "abcde" the number is "734". Try it and it works
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the value to find table[i] from 15 address
So this is the whole logic of the code revision engineered I will post the full writeup maybe tmrw.