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counting iteration of a number within an array

ralphcma (6)
I have been trying to get this to function. I however seem to be re displaying the array rather than it given me a count of each number. so for instance the array is populated by 1,2, 2,4,7,9, 9, 9, 11, 12 , 13, 13 , 15, 16, 16 , 16, 16, 19, 20

it will display 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
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        |     Number     |     Count     |
        ----------------------------------
        |      20        |      20       |
        |      19        |      19       |
        |      18        |      16       |
        |      17        |      16       |
        |      16        |      16       |
        |      15        |      16       |
        |      14        |      15       |
        |      13        |      13       |
        |      12        |      13       |
        |      11        |      12       |
        |      10        |      11       |
        |       9        |      13       |
        |       8        |       9       |
        |       7        |       9       |
        |       6        |       9       |
        |       5        |       7       |
        |       4        |       4       |
        |       3        |       2       |
        |       2        |       2       |
        |       1        |       1       |
        ----------------------------------

What it should display however is:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
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23
 
      
        |     Number     |     Count     |
        ----------------------------------
        |      20        |       1       |
        |      19        |       1       |
        |      18        |       0       |
        |      17        |       0       |
        |      16        |       4       |
        |      15        |       1       |
        |      14        |       0       |
        |      13        |       2       |
        |      12        |       1       |
        |      11        |       1       |
        |      10        |       0       |
        |       9        |       3       |
        |       8        |       0       |
        |       7        |       1       |
        |       6        |       0       |
        |       5        |       0       |
        |       4        |       1       |
        |       3        |       0       |
        |       2        |       2       |
        |       1        |       1       |
        ----------------------------------

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  void display_frequency(const int number_list[])
{
    for(int i=20;i > 0; i--)
        cout << "\t" << "|"<< setw(8) << i << setw(9)<< "|" << setw(8)
			 << number_list[i]<< setw(8) << "|" << endl;
 }


my random generator to populate the array is:
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void load_array(int number_list[])//populate the array
{
	int x=0;
	srand ((unsigned)time(0));
	for(int x = 0; x < SIZE; x++)
		number_list[x]=(rand() % 20+1); // 1-20
}


I would like to point out I am not using classes or anything to that effect. this is rather simple in practice I am just missing something
Last edited on
tallyman (99)
The problem is that you're loading the array differently then you want to. What you are doing now is loading each element with it's own value of 1-20. What you want to do is increment the element when the number is rolled.

So, instead of 
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for(int x = 0; x < SIZE; x++)
    number_list[x]=(rand() % 20+1); // 1-20

you should do something like 
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for(int x = 0; x < SIZE; x++) {
    int randNum = rand() % 20+1); // 1-20
    ++number_list[randNum - 1];
}
alex067 (401)
Is your Number array initialized from 0-20?

I don't see anything wrong with your load_array function, except you need to pass it by reference

Also, how are you checking it? You would need to use a nested for loop, where the first loop will hold the first index of the random array, then check 0-20 of the number array and see which matches, if it matches, you simply increment the number array index
alex067 (401)
Also it should be number_list[x] = rand()%20+1; idk if the parenthesis around the whole thing is necessary or even correct
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