torn grotto
Hey, I have a homework assignment in which I have to make a train ticket reservation system. I made a menu to display the trains currently available in the system (like a timetable). I wanted to use fix width columns, but regardless of what or how I try, the lines are just not aligned
Any idea why? Thanks for the help in advance
worn spruceBOT
torn grotto
tardy dagger
This happened to me too, I played with the setw() and fixed it, I think I was not accounting for the last column or something: #cpp-help-text message
Sorry I can't help more, I suck, but if that helps any
This is how it the setw() looked when I fixed it
torn grotto
I am assuming my problem originates from setw switching between strings and integers
Because that’s where the problem occours
woven pike
This is probably more of an issue that relates to utf8 if that's what encoding is being printed for that text. I believe setw()'s parameter corresponds to a byte length, not truly a character length. A utf-8 "character" could be anywhere from 1-4 bytes. If you notice where the alignment gets thrown off is anywhere a non-ascii character seems to exist in the string that comes before it
If you're allowed to use std::print, there's a pretty good chance it handles this correctly with utf8 text
torn grotto
I have tried it before with this:
void Menetrend::menetrendKiir() const { //FIXME: elcsúszik a kiírás
printf("Vonatok száma: %d\n", this->vonatokSzama);
printf("Vonatok:\n\n");
printf("%-15s%-13s%-23s%-25s%-17s%-18s%-16s%-2s\n",
"Név", "Vonatszám", "Indulási állomás", "Érkezési állomás",
"Indulási idő", "Érkezési idő", "Állapot", "Vagonok száma");
if (this->vonatokSzama == 0) {
printf("\x1b[37;41m%s\x1b[0m\n\n", "-----------------------------------------------------------------------------------------------------------------------------");
printf("Nincs egyetlen vonat sem!\n\n");
return;
} else {
printf("\x1b[37;40m%s\x1b[0m\n", "-----------------------------------------------------------------------------------------------------------------------------");
for (int i = 0; i < this->vonatokSzama; i++) {
printf("%-14s%-12d%-20s%-22s%-15s%-15s%-17s%-2d\n",
this->vonatok[i].getNev().c_str(), this->vonatok[i].getVonatSzam(),
this->vonatok[i].getIndulasiAllomas().c_str(), this->vonatok[i].getErkezesiAllomas().c_str(),
this->vonatok[i].getIndulasiIdo().getIdoString().c_str(), this->vonatok[i].getErkezesiIdo().getIdoString().c_str(),
this->vonatok[i].getAllapotString().c_str(), this->vonatok[i].getVagonokSzama());
}
}
printf("\n");
}
this is the result
woven pike
;compile clang_trunk -std=c++23 -stdlib=libc++
#include <iostream>
#include <iomanip>
#include <ios>
#include <locale>
#include <print>
int main()
{
std::locale::global(std::locale("en_US.UTF-8"));
::printf("%-15s%-13s%-23s%-25s%-17s%-18s%-16s%-2s\n",
"Név", "Vonatszám", "Indulási állomás", "Érkezési állomás",
"Indulási idő", "Érkezési idő", "Állapot", "Vagonok száma");
::printf("%-15s%-13s%-23s%-25s%-17s%-18s%-16s%-2s\n",
"aaaa", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa");
::printf("%-15s%-13s%-23s%-25s%-17s%-18s%-16s%-2s\n",
"Név", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa", "aaaa");
::printf("\n");
std::cout << std::setw(15) << std::left << "Név"
<< std::setw(13) << std::left << "Vonatszám"
<< std::setw(23) << std::left << "Indulási állomás"
<< std::setw(25) << std::left << "Érkezési állomás"
<< std::setw(17) << std::left << "Indulási idő"
<< std::setw(18) << std::left << "Érkezési idő"
<< std::setw(16) << std::left << "Állapot"
<< std::setw(02) << std::left << "Vagonok száma" << '\n';
std::cout << std::setw(15) << std::left << "aaaa"
<< std::setw(13) << std::left << "aaaa"
<< std::setw(23) << std::left << "aaaa"
<< std::setw(25) << std::left << "aaaa"
<< std::setw(17) << std::left << "aaaa"
<< std::setw(18) << std::left << "aaaa"
<< std::setw(16) << std::left << "aaaa"
<< std::setw(02) << std::left << "aaaa" << '\n';
std::cout << std::setw(15) << std::left << "Név"
<< std::setw(13) << std::left << "aaaa"
<< std::setw(23) << std::left << "aaaa"
<< std::setw(25) << std::left << "aaaa"
<< std::setw(17) << std::left << "aaaa"
<< std::setw(18) << std::left << "aaaa"
<< std::setw(16) << std::left << "aaaa"
<< std::setw(02) << std::left << "aaaa" << '\n';
::printf("\n");
std::print("{:<15}{:<13}{:<23}{:<25}{:<17}{:<18}{:<16}{:<2}\n",
"Név", "Vonatszám", "Indulási állomás", "Érkezési állomás",
"Indulási idő", "Érkezési idő", "Állapot", "Vagonok száma");
std::print("{:<15}{:<13}{:<23}{:<25}{:<17}{:<18}{:<16}{:<2}\n",
"aaaa", "bbbb", "cccc", "dddd", "eeee", "ffff", "gggg", "hhhh");
std::print("{:<15}{:<13}{:<23}{:<25}{:<17}{:<18}{:<16}{:<2}\n",
"Név", "bbbb", "cccc", "dddd", "eeee", "ffff", "gggg", "hhhh");
}
mild whaleBOT
woven pike
it'll be easier to view the output of those from here since it's getting truncated in discord: https://godbolt.org/z/jfnWErvrM
the middle row in all 3 is the one you can go off of as being correctly aligned/spaced apart. notice how the top two examples (printf and std::cout) are misaligned, but std::print() is aligned properly for all 3 rows... that just comes down to std::print / std::format internally handling utf-8 properly when working with unicode.
the reason this type of thing matters is that even though it seems like "Név" is 3 characters in length, it's size in bytes is 5. so the spacing gets thrown off just from that starting at the very beginning of the row.
azure copper
If you're allowed to use std::print, there's a pretty good chance it handles thi...
He isn't
We can go up to C++17, std::print is C++20
torn grotto
the reason this type of thing matters is that even though it seems like `"Név"` ...
Get it now
And indeed, if I remove letters suck as á é ó etc, and replace with a e o etc, then it works perfectly
I'll try to find a solution for this then, thanks
torn grotto
He isn't
We can go up to C++17, std::print is C++20
Most mondtam volna, hogy gyulának nem tűnik fel, csak gondolom a jporta 17-ig fordít, right?
azure copper
✅
torn grotto
iron remnant
download fmtlib :^)
torn grotto
will check it out, thanks
azure copper
download fmtlib :^)
His instructor didn't allow him to use sqlite because they(the instructor) couldn't understand what it did
So I doubt they will be allowed to use any libraries sadly
iron remnant
💀
torn grotto
if I don't tell him, he simply won't notice or realize
azure copper
torn grotto
even if I used sqlite, he wouldn't have noticed I'm sure lol
azure copper
Maximal Gyula, Minimal Effort ☝️
torn grotto
azure copper
Tbh I doubt he will actually look at the whole codebase of 30+ students
iron remnant
You could grab a function like this https://stackoverflow.com/a/5117542
to get the number of code units instead of bytes, that would work for simple things (but not for complex unicode sequences with multiple combining characters)
torn grotto
He will for some for sure, but I'm almost certain that he will not look at mine
Like he didn't do it so far, but rejected other students' works so far
iron remnant
(also this is assuming you are actually using UTF-8, whiuch isn't the default in MSVC / VS)
torn grotto
You could grab a function like this <https://stackoverflow.com/a/5117542>
to get...
Yeah, I think I tried to do something similar
what I did it I measured the "length" of the word I'm trying to print and then (after some math) set setw based on the return integer
but it didn't really work out
torn grotto
(also this is assuming you are actually using UTF-8, whiuch isn't the default in...
Correct
setlocale(LC_ALL, "hu_HU.utf8");
iron remnant
ah so you're not on windows
iron remnant
because windows + utf-8 + console is a whole other bag of worms 😄
azure copper
because windows + utf-8 + console is a whole other bag of worms 😄
Windows + utf8 is already a big enough bag 💀
Especially when I'm alternating between Manjaro(desktop) and Windows (portable)
Thankfully someone showed me how to set utf8 as default on win
worn spruceBOT
@torn grotto Has your question been resolved? If so, type !solved :)
azure copper
https://godbolt.org/z/rWh7fhhWT
I'll put this in my random_useful.h
iron remnant
you could probably make it work with setw, too, but you'd have to account for setw padding based on the number of bytes
torn grotto
https://godbolt.org/z/rWh7fhhWT
wow thank you
will try it later today
maybe I shouldn't have tried to make this function half past midnight
iron remnant
I'll put this in my `random_useful.h`
again, warning sticker, doesn't take into account if you have like combining marks as separate code units
for wide characters, there's a wcwidth function that sort of tells you this properly, but who wants to use wide characters 💀
torn grotto
https://godbolt.org/z/rWh7fhhWT
works flawlessly, thanks again
worn spruceBOT
@torn grotto Has your question been resolved? If so, type !solved :)
torn grotto
!solved