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# Manipulations with arrays!

Greenhorn
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(b) Suppose a is an array of ints such that 0<= a[i]<= 9.

(i) Write a code fragment to determine how many elements of the array have
value 5.

(ii) Write a code fragment to determine how many elements of a have been
assigned each decimal digit, i.e. how many elements have been set to 0,
how many have been set to 1, etc.

I m prepering to exam now))
Thanks a lot!

author and iconoclast
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Show us what you have so far, please.

Ibragim Gapuraev
Greenhorn
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Ernest Friedman-Hill wrote:Show us what you have so far, please.

I tried this:
i)
int[] list = {1,2, 4, 5, 6,5, 7, -2,9};
for(int i = 0; i<list.length;i++)
if(i == 5){
System.out.println(i);

but this gives me just the number, not quantity.
about (ii) I have no idea.>

Ernest Friedman-Hill
author and iconoclast
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OK, that's a good start. You need to declare an int variable "count" before your loop, and then in the loop, instead of printing something, add one to "count". Then after the loop, print the value of "count" -- that'll be the answer.

Part two is just the same, except you need one variable like "count" for each of the ten digits. How could you store all ten variables easily?

Ibragim Gapuraev
Greenhorn
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I got it! Thank you!)

Ibragim Gapuraev
Greenhorn
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I solved it like this:
(i)

(ii)

[ EFH: Added code tags ]

Ernest Friedman-Hill
author and iconoclast
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That looks great!

Marshal
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Good stuff , but always use the .length field in a for loop. That way you are protected against out of bounds Exceptions.