Current Events > I hate programming.

(+) Yeah! (+)

Don't know why i want to do this for a living.

Gotta get the length and width of a rectangle from user.
Call a function to double the entered length and width (return type void, must be passed by address/pointer)
Call another function to calculate area of new enlarged rectangle(must be passed by value)
Display new height, length, area.

I got this so far, and im stuck. I know my variable names suck.

#include <iostream>
using namespace std;
void doublelw(int *pl,int *pw,int *pl2,int* pw2);
int calcarea(int na);

int main()
{
int l,w,na,pl2,pw2;
cout<<"Enter Length and Width";
cin>>l>>w;
doublelw(&l,&w,&pl2,&pw2);
calcarea (na);
cout<<"Length:"<<pl2<<"Width:"<<pw2<<"Area:"<<na;
}
void doublelw(int *pl,int *pw,int* pl2, int* pw2)
{
*pl2= *pl * 2;
*pw2= *pw * 2;
}
int calcarea(int na)
{
pl2*pw2 = na;
return na;
}
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should have done pro gaming instead
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#include <iostream>
using namespace std;
void doublelh(int *plen,int *phei,int *plen2,int* phei2);
int calcarea( int len, int hei);

int main()
{
int len,hei,na,plen2,phei2;
int *pllen = &len;
int *phei = &hei;
cout<<"Enter Length and height"<<"\n";
cin>>len>>hei;
doublelh(&len,&hei,&plen2,&phei2);
na=calcarea (len,hei);
cout<<"Length:"<<plen2<<"\t"<<"Width:"<<phei2<<"\t"<<"Area:"<<na;
}
void doublelh(int *plen,int *phei,int* plen2, int* phei2)
{
*plen2= *plen * 2;
*phei2= *phei * 2;
}
int calcarea( int len, int hei)
{

return (len*hei);
}

Almost got it, but the Area it's calculating is the width and length of the original values.
---

I'm in IT and hated it too in college.
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LookANinja posted...

int calcarea( int len, int hei)
{

return (len*hei);
}

Almost got it, but the Area it's calculating is the width and length of the original values.

That's because you're using the variables for the width and length of the original values. What did variables did you save the doubled versions in?
---

For some reason i thought using pointers in the first function would change the value of the variable at that address. So len and hei will become the double of whatever was originally input.

#include <iostream>
using namespace std;
void doublelh(int *plen,int *phei,int *plen2,int* phei2);
int calcarea( int len, int hei);

int main()
{
int len,hei,na,plen2,phei2;
cout<<"Enter Length and height"<<"\n";
cin>>len>>hei;
doublelh(&len,&hei,&plen2,&phei2);
int *plen = &len;
int *phei = &hei;
na=calcarea (plen2,phei2);
cout<<"Length:"<<plen2<<"\t"<<"Width:"<<phei2<<"\t"<<"Area:"<<na;
}
void doublelh(int *plen,int *phei,int* plen2, int* phei2)
{
*plen2= *plen * 2;
*phei2= *phei * 2;
}
int calcarea( int plen2, int phei2)
{

return (plen2*phei2);
}

I got it working like this, but does it still fulfill the requirements of the assignment?
1st function pass by pointer
2nd function pass by value
---

It looks fine to me.
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I love programming because it's so easy

Alright thanks for your help! My next assignment will be similar, but with volume and using pass by reference. Hopefully it's not too complicated. D:
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Programming jobs pay you 6 figures for easy shit.

What programming tool are you using?
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lol if you can't do this you should really reconsider what you're doing with your life
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Ben111 posted...

What programming tool are you using?

Codeblocks.

I feel too old to be reconsidering my life choices >_<
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LookANinja posted...

Codeblocks.

Use Visual Studio

Wow, looking at the work programmers do...god damn, I'm surprised y'all don't want to kill yourselves.
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Vita_Aeterna posted...

Wow, looking at the work programmers do...god damn, I'm surprised y'all don't want to kill yourselves.

Idk I am just starting out and it is not that hard. But I literally just started this quarter this month so I am still very inexperienced. So far I think it is fun
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I.. i don't know.
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Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.
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Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging
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Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

This is something I should do, but right now I have other priorities. I'm basically the only actual programmer at my company, the other guys are like math/science people who put everything in one gigantic function and repeat a lot of code.
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LookANinja posted...

(return type void, must be passed by address/pointer)

That's just asking for null pointers and memory leaks.

should've used Rust
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please name your variables better tc because yikes
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Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

I do this, but mainly because I'm not a programmer and only use Matlab and python.
---

Sativa_Rose posted...

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

There's where understanding algorithms helps.
Knowing what's going in, what's supposed to come out, and all the steps needed in between, is far more important than the actual "coding" bits.

Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

use both. I have logging facilities in place to give me an idea of what's going on and to narrow down the problem, then when things go askew I fire up the debugger

Have you considered passing your doubled width/height variables by reference, or is that not allowed?
---

treewojima posted...

Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

use both. I have logging facilities in place to give me an idea of what's going on and to narrow down the problem, then when things go askew I fire up the debugger

With the current system I am working on, I usually have to have it running for like 6 hours before any bugs start to show up. So I've been exclusively using logging since I don't even know how you would use a debugger in a situation like that.

It's a system where I have a client constantly sending data over TCP to a server that then does some shit with it and sends some results back.
---

treewojima posted...

Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

use both. I have logging facilities in place to give me an idea of what's going on and to narrow down the problem, then when things go askew I fire up the debugger

i didnt mean to imply that printing things is never a good idea because you're exactly right -- logging is also invaluable.

Sativa_Rose posted...

I don't even know how you would use a debugger in a situation like that.

remote debuggers are a thing and are really neat.
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Sativa_Rose posted...

treewojima posted...

Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

use both. I have logging facilities in place to give me an idea of what's going on and to narrow down the problem, then when things go askew I fire up the debugger

With the current system I am working on, I usually have to have it running for like 6 hours before any bugs start to show up. So I've been exclusively using logging since I don't even know how you would use a debugger in a situation like that.

It's a system where I have a client constantly sending data over TCP to a server that then does some shit with it and sends some results back.

Use those logs to cook up erroneous data or activity, then create some unit tests or debugging backdoors to "force" the application to behave that way on demand?

bobtuse posted...

Have you considered passing your doubled width/height variables by reference, or is that not allowed?

that's what i'm doing for the next assignment (Cube, and the entered w/l/h is halved instead of doubled) I think that's what i was thinking when i said i thought pass by pointer would change the value at the address, but it's pass by reference that does that right?
---

treewojima posted...

Sativa_Rose posted...

treewojima posted...

Giant_Aspirin posted...

Sativa_Rose posted...

Coding is cool dude, though this is coming from someone who still debugs using print statements rather than an actual debugging tool.

But yeah, just throw some print statements in there to figure out what the F is going wrong, and then fix it, and then move on to the next problem. That's what I do. Persistence is key.

or learn to use a debugger. it's an invaluable tool. once i learned to use one i never, ever, ever went back to printing out stuff as a means of debugging

use both. I have logging facilities in place to give me an idea of what's going on and to narrow down the problem, then when things go askew I fire up the debugger

With the current system I am working on, I usually have to have it running for like 6 hours before any bugs start to show up. So I've been exclusively using logging since I don't even know how you would use a debugger in a situation like that.

It's a system where I have a client constantly sending data over TCP to a server that then does some shit with it and sends some results back.

Use those logs to cook up erroneous data or activity, then create some unit tests or debugging backdoors to "force" the application to behave that way on demand?

This is the kind of thing I need to start doing. I have to up my game a bit.
---

LookANinja posted...

bobtuse posted...

Have you considered passing your doubled width/height variables by reference, or is that not allowed?

that's what i'm doing for the next assignment (Cube, and the entered w/l/h is halved instead of doubled) I think that's what i was thinking when i said i thought pass by pointer would change the value at the address, but it's pass by reference that does that right?

Think about what you are passing to a function. Are you passing just a value, or are you passing an address that contains the value you are wanting to work with?
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LookANinja posted...

bobtuse posted...

Have you considered passing your doubled width/height variables by reference, or is that not allowed?

that's what i'm doing for the next assignment (Cube, and the entered w/l/h is halved instead of doubled) I think that's what i was thinking when i said i thought pass by pointer would change the value at the address, but it's pass by reference that does that right?

You can change the value either way, although you'll have to dereference the pointer. What makes passing by ref simpler in many cases is that you know it will be a valid piece of memory. The advantage of pointers is that they can be set to a null value and updated after initialization.
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tag
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bobtuse posted...

LookANinja posted...

bobtuse posted...

Have you considered passing your doubled width/height variables by reference, or is that not allowed?

that's what i'm doing for the next assignment (Cube, and the entered w/l/h is halved instead of doubled) I think that's what i was thinking when i said i thought pass by pointer would change the value at the address, but it's pass by reference that does that right?

You can change the value either way, although you'll have to dereference the pointer. What makes passing by ref simpler in many cases is that you know it will be a valid piece of memory. The advantage of pointers is that they can be set to a null value and updated after initialization.

Now i'm worried i did the assignment wrong and was supposed to dereference the pointer.
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