Help with a java assignment?

Question

I having a problem with this particular method in my program. It keeps throwing the array out of bounds error and I can't figure out why. Can anyone fix this? Thank you.

Calculate the count of the each letter in str,
Check for letter, non-letter
*/
public void calCount(String str)
{
char ch = ' ';
int i = 0;
for(i = 0; i < str.length(); i++)
{
ch = str.toUpperCase().charAt(i);

if(Character.isLetter(ch))
{
count[i - 'A']++; // 'A' for 0, 'B' for 1, ... 'Z' for 25
}
else
{
count[count.length - 1]++;
}
}

}

Answer 1

The ASCII value for "A" is not 0, so when you do:

count[i - 'A']++; // 'A' for 0, 'B' for 1, ... 'Z' for 25

it's going WAY out of bounds.

Also, this isn't really what you want to be doing anyway, you want to compare it to 'ch', not 'i'

Answer 2

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Answer 3

If count is the array and holds only 26 then if A=65, you are way off.

If your string is apple, are you trying to use the ascii number of the letter as the index to put 1 in there, so if you get 2 letter P's you would have a 2 in there?

Then if so, it should be

count['A']++

I dont know why you would substract the size of count



I dont know what exactly count is. I'm just guessing.