Question

C ++

1. Write down the missing code according to the comments.

#include <cstdlib> #include <iostream> using namespace std; void fun1(int radius) {     /*     dynamic memory management     */     double * dmptr;     double circumference;         /*     add the code below to:     - allocate a memory location for a double and nameless variable in heap and assign its address to the pointer     - assign 3.14 to the variable in heap via the pointer.     */         /*     add the code below to:     - calculate the circumference of a circle. Its radius is from the parameter of this function and the value of pi is from the nameless variable in heap     */         /*     print the area     */     cout<<" circumference = "<< circumference <<endl;         delete dmptr;    } void fun2(int n) {     int sum = 0;     int *dmptr;         /* add the code below to:      allocate n memory locations for an integer and nameless array in heap via a pointer     */     /* add the code below to:      inializate the array in heap     */     for(int i=0; i<n; i++)     {          dmptr[i] = i * 2;   }                 /*     calculate the sum of the elements of the array in heap     */    /*     print the sum     */     cout<<"sum="<<sum <<endl;             delete[] dmptr;    } int main() {       fun1(2);     fun2(5);         return 0; }

Answer 1

//################## PGM START ##########################################

#include <cstdlib>
#include <iostream>

using namespace std;

void fun1(int radius){

    /*
    dynamic memory management
    */
    double * dmptr;
    double circumference;

    /*
    add the code below to:
    - allocate a memory location for a double and nameless variable in heap and assign its address to the pointer
    - assign 3.14 to the variable in heap via the pointer.
    */
    dmptr=new double();
    *dmptr=3.14;

    /*
    add the code below to:
    - calculate the circumference of a circle. Its radius is from the parameter of this function and the value of pi is from the nameless variable in heap
    */
   circumference=2*(*dmptr)*radius;

    /*
    print the area
    */
    cout<<" area = "<<(*dmptr*radius*radius)<<endl;
    cout<<" circumference = "<< circumference <<endl;

    delete dmptr;
}

void fun2(int n){

    int sum = 0;
    int *dmptr;

    /* add the code below to:
     allocate n memory locations for an integer and nameless array in heap via a pointer
    */
    dmptr=new int[n];

    /* add the code below to:
     inializate the array in heap
    */
    *dmptr={0};

    for(int i=0; i<n; i++)    {

         dmptr[i] = i * 2;
   }      
    /*
    calculate the sum of the elements of the array in heap
    */
    for(int i=0;i<n;i++){
       sum+=dmptr[i];
   }

   /*
    print the sum
    */
    cout<<" sum="<<sum <<endl;

    delete[] dmptr;
}

int main(){

    fun1(10);
    fun2(5);

    return 0;
}

//############################### PGM END ####################################

OUTPUT

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