Converting an array with elements to uppercase.C

[FreQUENCY]

Lets suppose that i have an array 

char words[W][9 + 1];

W is defined to 5. Words is filled with a scanf loop. I can not make the inputed data to this array uppercase. Any idea?

 

[FreQUENCY]

If i loop over the elements and use 

words[i]=touper(words[i]) 

i will get an error !

[WereCatf]

7 minutes ago, FreQUENCY said:

If i loop over the elements and use 

words[i]=touper(words[i]) 

i will get an error !

First of all, toupper() only converts a single character, not a string. Secondly, you're not iterating over the characters.

 

The following will do it for you:

for(int i=0; i<5; i++)
	for(int j=0; j<9; j++)
		words[i][j] = toupper(words[i][j]);

 

[FreQUENCY]

rtfm.I have a ton of shit to do with university. Trust me ,i aint giving up so easy.Thank you for the correction.

@James Evens

[Unimportant]

10 minutes ago, FreQUENCY said:

If i loop over the elements and use 

words[i]=touper(words[i]) 

i will get an error !

toupper works on a single character. You need to write a function that loops over all characters in a string and converts them to uppercase:

 

//Include ctype.h for toupper
#include <ctype.h>

//Function takes a c string pointer and converts it to uppercase
void
strtoupper(char* str)
{
	while (*str)
	{
		*str = toupper(*str);
		++str;
	}
}

//Example use in your case:
strtoupper(words[i]);

 

[FreQUENCY]

1 minute ago, WereCatf said:

First of all, toupper() only converts a single character, not a string. Secondly, you're not iterating over the characters.

 

The following will do it for you:

for(int i=0; i<5; i++)
	for(int j=0; j<9; j++)
		words[i][j] = toupper(words[i][j]);

 

I am off to a math class.I will test your code when i arrive. Thank you very much @WereCatf

[WereCatf]

2 minutes ago, Unimportant said:

while (*str)

That's a little risky. If OP somehow messes up and there's no NULL-character stored in the array, you'll end up overwriting who knows how much memory with that and crashing. That is the cleaner approach for someone who knows to always make sure there is a NULL there, but for the OP, I believe sticking to specific depth, like in my approach, is better while they're still learning.

[Unimportant]

19 minutes ago, WereCatf said:

That's a little risky. If OP somehow messes up and there's no NULL-character stored in the array, you'll end up overwriting who knows how much memory with that and crashing. That is the cleaner approach for someone who knows to always make sure there is a NULL there, but for the OP, I believe sticking to specific depth, like in my approach, is better while they're still learning.

Presumably he'll want to print the result after converting it to uppercase.

He'll get the same surprise when printf does not find a terminating 0.

[WereCatf]

Just now, Unimportant said:

Presumably he'll want to print the result after converting it to uppercase.

He'll get the same surprise when printf does not find a terminating 0.

Yeah, but at least he's not overwriting random memory, only printing it.

[Unimportant]

Just now, WereCatf said:

Yeah, but at least he's not overwriting random memory, only printing it.

Doesn't really matter. It'll simply crash with a segfault both ways.

Your application can't mess with another application or the OS's memory if that is your fear.

[WereCatf]

Just now, Unimportant said:

Your application can't mess with another application or the OS's memory if that is your fear.

I know.