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HELP: Arrays Program -- I need help with it all...I don't think my code is formatted correctly, and it won't output last part

artebellezza (4)
I apologize profusely in advance for how long this is...I am so lost :( :( :(

This is due in 15 minutes, and I have been working on it since assigned, but still struggling. I don't have classmates or a way to contact my professor, as I am the only student taking it online.

Can anyone please help?? I am so lost.

I do not know how to output the last parts he wants me to show -- and I am not sure I am understanding his instructions correctly and following them right:

Here is my professor's assignment:

Write a program that makes an array of 25 random integers each from 3 to 7 (use your function randint() to generate these numbers).

Your program

A) declares the array in the main (you are not allowed to use global variables!),

B) initializes the above array to random values 3 to 7 using your randint() function

C) and then calls the functions with the provided prototypes to do the following:

show the original array,
show the array in reverse,
shows the lowest value in the array,
shows the highest value in the array,
shows the sum of all numbers in the array,
shows the average of all number in the array
shows how many times the number 5 appears in the array
shows the difference between the First and Last elements of the array
shows the elements of the array before a specified index
shows the message "I am now done with CSS1! :)"

For this, you must write the function definitions for the prototypes provided below (each function is worth 10 points...So, 10pts extra credit):

void showArray ( int a[ ], int size ); // shows the array in the format "int a [ ] = { 3, 7, 4, ... ,5, 6, 3, 4, 7 } "

void showReverse ( int a[ ], int size ); // shows the array in reverse using the format "int a [ ] = { 7, 4, 3, 6, 5, ... , 4, 7, 3 } "

int lowest ( int a[ ], int size ); // finds and returns the lowest value in the array (should be 7)

int highest ( int a[ ], int size ); // finds and returns the highest value in the array (should be 3)

int sumArray ( int a[ ], int size ); // calculates and returns the sum of all values in the array

float averageVal ( int a[ ], int size ); // calculates and returns the average of all values in the array

int count5 ( int a[ ], int size ); // returns how many times the number 5 appears in the array

int firstMinusLast ( int a[ ], int size ); // returns the difference between the First Array Element - Last Array Element

void showBeforeIndex( int a [ ], int size, int index); // shows all array values before a specified index

void done ( ); // a function that shows the message "I am now done with CSS1! :)

int randint(int min, int max); // a function that returns a random integer between min and max



Sample Program Run:

Making an array of 25 random integers from 3 to 7!
Original array a [ ] = { 3, 7, 5, 6, 3, 4, 4, 3, 5, 5, 6, 5, 5, 7, 3, 5, 3, 6, 4, 5, 7, 4, 7, 3, 5 }
Reversed array a [ ] = { 5, 3, 7, 4, 7, 5, 4, 6, 3, 5, 3, 7, 5, 5, 6, 5, 5, 3, 4, 4, 3, 6, 5, 7, 3 }
Lowest value is 3
Highest value is 7
The sum of all array elements is 120
The average of all array values is 4.8
The number 5 appears 8 times.
The difference between the first and last array elements is -2
The array values before Index 3 are 3, 7, 5
I am now done with CSS1! :)
*/

My code so far:

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  /*


    #include <time.h>
    #include <iostream>
    #include <stdlib.h>
    using namespace std;

    void showArray ( int a[ ], int size ); // shows the array in the format "int a [ ] = { 3, 7, 4, ... ,5, 6, 3, 4, 7 } "

    void showReverse ( int a[ ], int size );

    int  lowest ( int a[ ], int size );

    int highest ( int a[ ], int size );

    int  sumArray ( int a[ ], int size );

    float averageVal ( int a[ ], int size );

    int count5 ( int a[ ], int size );                                                 // returns how many times the number 5 appears in the array

    int firstMinusLast ( int a[ ], int size );                                    // returns the difference between the First Array Element - Last Array Element

    void showBeforeIndex( int a [ ], int size, int index);            // shows all array values before a specified index

    void done ( );                                                                           // a function that shows the message "I am now done with CSS1! :)

    int randint(int min, int max);                                                  // a function that returns a random integer between min and max


    int main ()
    {
        srand((int)time(NULL));
        int i=0;
        const int size = 25; // size variable for arrays
        int randint[size], lowest, highest;


        cout << "Making an array of 25 random integers from 3 to 7!\n";
        cout << "\n";
        cout << "Original array a [ ] = {";

        for(i; i < size; i++)
        {
                // NOTE: randvalue[i] = rand () % 3 + 5 is NOT correct. switch 3 and 5.
                randint[i] = 3 + rand () % 5; // random number between 3 to 7
        }

         showArray(randint, size); // pass the array and its SIZE to function
         cout << "}\n";

        // Reversed array
         // One way to reverse an array is to swap the first and last value,
        // then swap the second and second-to-last value,
        // then swap the third and third-to-last value, and so on...
        cout << "\n" << "Reversed array a [ ] = { ";

        int j = size-1; // initialize j to the last index
        i = 0;  // set i to the beginning index (i.e. index 0)

        while( i <= j)  // keep loop until i and j cross over
        {
            std::swap(randint[i], randint[j]); // swap the values at i-th and j-th index
            i++; // move i forwards
            j--; // move j backwards
        }

        showReverse(randint, size);
        cout << "}\n";

        lowest=randint[0];
        highest=randint[0];

        for (i = 0; i < size; i++)
        {
            if(randint[i]<lowest)
                lowest=randint[i];
            if(randint[i]>highest)
                highest=randint[i];
        }

        cout<<"\nLowest value is : "<<lowest <<"\n";
        cout<<"\nHighest value is : "<<highest <<"\n";


        int sum=0;


        for (int a=0; a<size; a++)
        {
			sum+=randint[a];
        }

        cout << "\nThe sum of all array elements is " << sum << endl;

        float average=sum/size;

        cout << "\nThe average of all array values is " << average << endl;

        /*firstMinusLast(int a[0], int size);*/

        showBeforeIndex;

        done;

        return 0;
    }

    // Function definitions
    void showArray ( int a[ ], int size )
    {
         for(int i = 0; i < size; i++) std::cout << a[i] << " ";
    }

    void showReverse ( int a[ ], int size )
    {
         for(int i = 0; i < size; i++) std::cout << a[i] << " ";

    }

    int count5 ( int a[5], int size )
    {   /*
        int counter = 0;
        for(int i = 0; i < size; i++)
            if(randint[i] == numsearch)
                counter++;
        return counter;
        */

        int counter = 0;
        int numseach = 5;
        for(int i = 0; i < size; i++)
            if(randint[i] == numsearch)
                counter++;
        std::cout << "\nThe number 5 appears " << counter <<" times.\n";
    }

    int firstMinusLast(int a[], int size)
    {
        return(a[0] - a[size-1]);
        std::cout <<"\nThe difference between the first and last array elements is" << firstMinusLast << "\n";
    }


    void showBeforeIndex( int a [ ], int size, int index)  // shows all array values before a specified index
    {
        for(int Ix = 0; Ix < index; Ix++)
            cout << a[Ix] << " ";
    }                                                                         // a function that shows the message "I am now done with CSS1! :)

    void done ( )
    {
        std::cout << "I am now done with CSS1! :)\n";
    }

    int randint(int min, int max);
kbw (9488)
showArray(): ok.

showReverse(): the loop should go backwards from (size - 1)

lowest(): not implemented, but you start with a local varaible set to a[0], if any other element is lower, you assign it to that variable, then return it.

highest(): not implemented, but you start with a local varaible set to a[0], if any other element is higher, you assign it to that variable, then return it.

sumArray(): not implemented, but you start with a local varaible set to a[0], then add all the other elements to that variable, then return it.

averageVal(): not implemented: return (float)sumArray(a, size) / size; You need the cast to float to avoid truncation in the result.

count5(): syntax error. Change randint[i] to a[i].

firstMinusLast(): ok

showBeforeIndex(): ok
icy1 (596)
This is OP's other post, which looks quite similar to this one... http://www.cplusplus.com/forum/beginner/237681/
At least a fix for firstMinusLast was made here.
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