Chapter ten exercise 13 a little help here before I peek at the answer.

[A31Chris]

Here is the output I'm getting from my solution to this. Its got me a little baffled why its converting every non cap to a lowercase 'a'.

Code: (Objective-C)

A Test To Remove All Non-Capitals!
Now Making All Capitals!
A Tααα Tα Rααααα Aαα Nαα-Cααααααα!

haha! gots me scratching my head a bit. OK I'll be back in a few days to see if anyone can give me a clue what I'm doing wrong.

Code: (Objective-C)

//Program to convert lowercase to upper case.

#include <stdio.h>

void upperCase(char string[80])
{
	int j;

	for(j=0;string[j]!='\0';j++)
	{
		if(string[j]>='a' && string[j]<='z')
			{
				string[j]=-'a'+'A';
			}
		

	}
	return;
}

int main(void)
{
	char testString[80]="A Test To Remove All Non-Capitals!";

	printf("%s\n",testString);

	printf("Now Making All Capitals!\n");
	
	upperCase(testString);

	printf("%s",testString);
	
	
	getchar();
	return 0;
}

[Waiting]

That looks like an alpha symbol rather than an a.

What does   string[j]=-'a'+'A' do ?

[A31Chris]

Alright I've been trying to reply but this forum software is acting asinine.

It substracts the asci value of 'a' from the character variable c, then adds the asci value of 'A' to it. This formula produces the lowercase to capital letter result of alphabetic characters.

And I peeked at the answer after a few days of being stumped. My error was a syntax error.

string[j]=-'a'+'A';

should be:

string[j]=string[j]-'a'+'A';

[mitchb]

Hex 20 is the difference between lower case and upper case. The space character happens to be hex 20.

The statement string[j] = string[j]-'a'+'A'; the 'a' + 'A' can be replaced with a space.

string[j] = string[j]-' ';

Mitch