Question

I need this in C++

Write a function using the following structure and prototype.

struct Stats
{
    float avg;     //Average value of an integer array
    float median;  //Median value  of an integer array
    int   *mode;   //array containing the modes
    int   nModes;  //number of modes in the array
    int   maxFreq; //max frequency of modes
};

Stats *avgMedMode(int *,int); 

The function takes in an integer array and the size of the array.
Then returns a pointer to a structure containing the average, median
and mode.  You will then write a printStat() function that will print
the results contained in the stats structure.  I will input a small 
integer array to test this out so ask for how many inputs to fill the array, 
then the values to place into the array.  Make sure you delete the 
dynamic array creation for the mode when you exit the problem.

Note:  The array may have no modes, 1 mode or many modes.

Answer 1

#include<iostream>

#include<algorithm>

using namespace std;

struct Stats

{

    float avg;     //Average value of an integer array

    float median; //Median value of an integer array

    int   *mode;   //array containing the modes

    int   nModes; //number of modes in the array

    int   maxFreq; //max frequency of modes

};

Stats *avgMedMode(int *,int);

Stats *avgMedMode(int *a,int n)

{

               float avg=0,sum=0;

               for(int i=0;i<n;i++)

                              sum=sum+a[i];

//            cout<<"sum = "<<sum<<endl;

               avg=sum/n;

               sort(&a[0],&a[n]);//sort all the elements

//            for(int i=0;i<n;i++)

//                           cout<<a[i]<<" ";

               float median=0;

               if(n%2==0)

               {

                              int mid=n/2;

                              median=(a[mid]+a[mid-1])/2.0;

                              //if n is even, then median is the average of two middle values,

                              //here index starts from 0, so middle values are, eg. for n=10

                              //so index 0 to 9, middle are indexes 4 and 5, so 10/2=5 and 5-1=4

               }

               else

               {

                              median=a[n/2];//index starts at 0, so middle is n/2

               }

               int b[n][2];

               //b is 2d array has b[i][0] as the element itself from a[i]

               //and b[i][1] as its count calculated in the below loop

               int index=0;//index of b array

               int temp=a[0],count=1;

               //initially 1 element to temp, start i at 1

               //to compare, and count =1 (initially as the element is counted which is im temp)

               for(int i=1;i<n;i++)

               {

                              if(temp==a[i])

                              {

                                             count++;

                              }

                              else

                              {

                                             b[index][0]=temp;

                                             b[index][1]=count;

                                             index++;

                                             temp=a[i];

                                             count=1;

                                             //store the count and element in b, change temp and reset the count

                              }

                              if(i==n-1)//at the last element, we also need to store whatever is there in temp and count to b

                              {

                                             b[index][0]=temp;

                                             b[index][1]=count;

                                             index++;//now index is the count of all distinct elements, size of b

                              }

               }

//            for(int i=0;i<index;i++)

//                           cout<<b[i][0]<<" "<<b[i][1]<<endl;

               int maxCount=0;

               for(int i=0;i<index;i++)

               {

                              if(maxCount<b[i][1])

                                             maxCount=b[i][1];

               }

//            cout<<"max Count= "<<maxCount<<endl;

               int numberMaxCounts=0;//will store the number number of modes

               for(int i=0;i<index;i++)

                              if(b[i][1]==maxCount)

                              {

                                             numberMaxCounts++;

                              }

               int *mode;

               if(numberMaxCounts==index || n==0)//if all elements have equal count, then there is no mode

               {

                              mode='\0';

                              maxCount=0;

                              numberMaxCounts=0;

                              if(n==0)

                              {

                                             avg=0;

                                             median=0;          

                              }

               }

               else

               {

               int ind=0;

                              mode=new int[numberMaxCounts];

                              for(int i=0;i<index;i++)

                              {

                                             if(b[i][1]==maxCount)

                                                            mode[ind++]=b[i][0];

                              }                                                          

               }

              

               Stats *s=new Stats();

               s->avg=avg;

               s->median=median;

               s->maxFreq=maxCount;

               s->nModes=numberMaxCounts;

               s->mode=mode;

               return s;

}

void printStat(Stats s)

{

               cout<<"\nStats are :\n";

               cout<<"Average : "<<s.avg<<endl;

               cout<<"Median : "<<s.median<<endl;

               cout<<"Number of Modes : "<<s.nModes<<endl;

               cout<<"Max Frequency of mode : "<<s.maxFreq<<endl;

               if(s.mode=='\0')

                              cout<<"There is no mode!"<<endl;

               else

               {

                              cout<<"Mode : "<<endl;

                              for(int i=0;i<s.nModes;i++)

                                             cout<<"\t\t"<<s.mode[i]<<endl;

               }

                             

}

int main()

{

               int n;

               cout<<"Enter the size of array! : ";

               cin>>n;

               int *a;

               a=new int[n];

               cout<<"Enter its elements: \n";

               for(int i=0;i<n;i++)

                              cin>>a[i];

               Stats *s=avgMedMode(a,n);

               printStat(*s);

delete [](s->mode);

delete [](s);

}

//output