Frustrating issue with Arrays

[knightsb78]

Hey everyone!

Fairly new to Java and have been struggling with some of the array use issues.

I have 2 arrays the size of which is set by a SIZE variable:

2 Dimensional

Array 1: UserID[]
Array 2 TransAmount[]

Now I can loop through and printout the contents of these using a standard IF loop.

What i'm having trouble with is looping through and printing out the number of transactions for each unique UserID WITHOUT using a sort/list function and without altering the data structure.

What i've pretty much done to date is:

for(i=0;i<size;i++)
      {
    	  System.out.print(UserID[i]);
    	  System.out.print(", ");
    	  System.out.println(TransAmount[i]);

I would then try to setup a seperate For loop with a nested IF statement to basically increment a count value when comparing the previous userID with the next. and then print out the value etc. The problem is that this doesnt work for an unordered list where the userIDS appear multiple times. It also ends up just looping around and printing out every userid with the count.

Anyway, a little help or pointer in the right direction would be appreciated. Its definitely an issue with my logic for the loop so id appreciate some advice.

Would be so simple if i could sort the list etc.

Cheers

[mine0926]

I am not sure if I understand you correctly on what you want to do on your second loop but you might want to look at this.

[JosAH]

without altering the data structure.

What data structure? All I can see are two arrays and you want to keep them in 'parallel', i.e. A[n] should correspond with B[n] for all posssible values of n.

kind regards,

Jos