Solve all assignments and questions given in the c++ class

main.cpp

//
//  main.cpp
//  Algorithms
//
//  Created by Sanni Michael on 01/05/2019.
//  Copyright © 2019 Sanni Michael. All rights reserved.


/**** The programs written below makes use of functions which are later called in the main function. 
      This allows us to familiarize ourself with modular programming
      It also allow us to call the main function once instead of having to call it all the time which is cpu intensive
      *****/


#include <iostream>
#include <vector>
#include <numeric>
#include <string>

using namespace std;

// TEST : QUESTION 1
void testQuestionOne() 
{
    
    // List and compute the average of all integers from 1 to 50
    
    int sum = 0;
    
    int counter = 0;
    
    double average = 0.0;
    
    cout << "List And Average Of One To Fifty" <<endl;
    for (int k = 1; k<=50; k++) {
        cout << k << "\n";
        counter++;
        sum+=k;
    }
    
    average = sum / counter;
    
    cout << "\nAverage = " << average << "\n\n";
    
}


// TEST : QUESTION 2
void testQuestionTwo()
{
    
    int sum = 0;
    
    int count = 0;
    
    double avg = 0.0;
    
    cout <<"List And Average Of All Numbers Divisible By Three From Forty Nine To One" <<endl;
    
    for (int j = 49; j>=1; j--) {
        if(j % 3 == 0){
            cout << j << "\n";
            count++;
            sum+=j;
        }
    }
    
    avg = sum / count;
    
    cout << "\nAverage = " << avg << "\n\n";
    
}

// C++ PRACTICAL SOLUTIONS

void weekOne()
{
    
    int numberOfMonths;
    double payRise = 0.25;
    double sum = 0.0;
    
    cout << "Please Enter Number of Month : "; // This should be 7 according to the queation
    cin >> numberOfMonths;
    
    vector <double> monthArray(numberOfMonths);
    
    for (int i = 0; i < numberOfMonths; i++)
    {
        cout << "Month #" << i+1 << " ";
        cin >> monthArray[i];
    }
    
    //cout<<accumulate(monthArray.begin(),monthArray.end(),0); // This will print out the sum of all salaries in array
    for (size_t i=0; i<monthArray.size(); ++i)
    {
        sum+=monthArray[i] * payRise;
        //cout << monthArray[i] << endl; // For printing out individual elements in the vector/array
    }
    
    cout << "\nSum of backdated salary for the past seven months after pay rise "<<endl;
    cout << "\nSum : "<<sum<<endl;
    
}



void weekSix()
{
    
    // Program to welcome lecturer to class;
    char lecturerName[100];
    int gender;

    cout << "Enter Lecturer Name And Gender";
    cout << "\n NB : Enter 1 for male and 2 for female";
    cout << "\nLecturer Name ";
    cin >> lecturerName;
    cout << "\nLecturer Gender ";
    cin >> gender;
    
    switch (gender) {
        case 1:
            cout << "\nWelcome : Mr " << lecturerName << endl;
            break;
        case 2:
            cout << "\nWelcome : Mrs " << lecturerName << endl;
            break;
        default:
            cout << "\nWRONG INPUT" <<endl;
            break;
    }
      
    // Program to print Hello World;
     cout << "\nHello World"<<endl;
      

}

void weekSeven()
{
    
    // Program to find average of the scores of four exams taken by a student
    int sum = 0;
    
    double avg = 0.0;
    
    int scoreOne,scoreTwo,scoreThree,scoreFour;
    
    cout << "Enter Score 1 \n";
    cin >> scoreOne;
    cout << "Enter Score 2 \n";
    cin >> scoreTwo;
    cout << "Enter Score 3 \n";
    cin >> scoreThree;
    cout << "Enter Score 4 \n";
    cin >> scoreFour;
    
    sum = sum + scoreOne + scoreTwo + scoreThree + scoreFour;
    
    avg = sum / 4;
    
    cout << "Average of Scores = "<<avg<<endl;

}

// Call all user defined functions in the main function

int main() 
{
 
    testQuestionOne();
    testQuestionTwo();
    weekOne();
    weekSix();
    weekSeven();
    
    return 0;
}




// FIND THE AREA AND PERIMETER OF TRIANGLE USING C++ CLASS

#include <iostream>
#include <cmath>

using namespace std;

class AreaAndPerimeterOfTriangle
{ 
    public: 
    
    double sideA = 0.0;
    double sideB = 0.0;
    double sideC = 0.0;
    double perimeter = 0.0;
    double s = 0.0;
    double areaSum = 0.0;
      
    //Default Constructor 
    AreaAndPerimeterOfTriangle() 
    { 
        //cout << "Default Constructor will always be called" << endl;  
    } 
      
    //Parameterized Constructor 
    //Constructor to assign values to data members
    AreaAndPerimeterOfTriangle(double s1,double s2, double s3) 
    { 
        sideA = s1;
        sideB = s2;
        sideC = s3;
        //cout << "Parametrized Constructor called" << endl; 
    } 
    
    // Method to find perimeter of triangle
    void peri()
    {
        perimeter = sideA + sideB + sideC;
        cout << "Perimeter of the triangle is " << perimeter << endl; 
    }
    
    // Method to find area of triangle
    void area()
    {
        s = sideA + sideB + sideC / 2;
        areaSum = s * (s - sideA) * (s - sideB) * (s - sideC);
        cout << "Area of Triangle : "<< sqrt(areaSum) <<endl;
        
    }
}; 

// Test Driver
int main() { 
      
    // areaObject will call Default Constructor 
    AreaAndPerimeterOfTriangle areaObject; 
      
    // Create an instance of the AreaAndPerimaterOfTriangle class and initiliaze your Constructor
    // Parameterized Constructor 
    AreaAndPerimeterOfTriangle areaObject2(22.6,14.7,13.8); 
    
    // Call perimater of triangle
    areaObject2.peri(); // Perimeter of the triangle is 51.1 
    
    // Call area of triangle
    areaObject2.area(); // Area of Triangle : 925.307   
    
    return 0; 
}

 


/*****************************************************************************************************************************
                                          2018 C++ EXAMINATION ANSWERS
*****************************************************************************************************************************/



/*****************************
QUESTION 1 - German Questions
****************************/

i. object

ii. private and public
      
iii. 0
      
iv. name

v. local

vi. pointer

vii.  int mat1[4][3];

viii. main

ix.
      
//Function prototype declaration
double add(float a, float b, int c);

//Function prototype definition
double add(float a, float b, int c){
  double sum = 0;
  sum = a + b + c;
  return sum;
}

x.
      
//Function prototype declaration
void linearArray(int arr[]);

//Function prototype definition
void linearArray(int arr[]){
  for (int i = 0; i < ARRAYSIZE(arr); i++) {
      cout << " i "<< arr[i];
  }
}

xi. const double waterRate = 5.65;

xii. Bjarne Stroustrup at AT&T Labs

xiii. memory address

xiv.
      
      <conio.h>
      <ctype.h>
      <string.h>
      <math.h>
      <cmath>
      <stdlib.h>
      
xv. enum grade { A = 10, B = 12, C = 23 };
      
xvi. superset

xvii. <cmath>

xviii. break
      
xix. ampersand

xx. destructor




/*****************************
QUESTION 2 - True/False
****************************/



i. F
ii. F
iii. F
iv. F
v. F
vi. T
vii. F
viii. F
ix. F
x.F
xi. T
xii. F
xiii. F
xiv. T
xv. F
xvi. T
xvii. F
xviii. T
xix. T
xx. T



/*****************************
QUESTION 3
****************************/

3a.
3b. int
    short int
    long int
    signed long int
    unsigned long int
    
    char
    wchar_t
3c. n--;
    --n;
    n = n - 1;
    n-=1;

/*****************************
QUESTION 4
****************************/
4a.
      
#include <iostream>
#include <cmath>

using namespace std;

int main(){
  
      double array[25];

      for (int z = 0; z < 25; z++) {
           cin >> array[z];
      }

      // Print array in reverse order
      for (int i = 24; i >= 0; i--) {
        cout << "\ni = " <<array[i]<<endl;
      }
      
      return 0;
}

4b. x = 8, y = 3;
i. x*=x+y--; 

    int x = 8;
    int y = 3;
    
    int expr = x*=x+y--;
    cout << expr << endl; // 88
    why? 
          same as x = x * x+y--// NB; dont solve it this way, you will get an entirely diff answ
          according to operator preceedence assignment operators are 16th on the table so that means it executes operands 
          without assignment first which is x+y = 11; y-- means assign 3 to y before decrementing, --y means decrement before
          assigning to y.then x+y = 11 * x which gives 88. Because we are assigning the result to x, the value of y will not
          be decremented except when printed on the next line
          https://github.com/MicrosoftDocs/cpp-docs/blob/master/docs/cpp/cpp-built-in-operators-precedence-and-associativity.md
          
ii. x/=++y;
    answer = 2
    why?
          increment first before assigning then dividing by 8 which is 8/4 = 2;

iii. y+=y-x++
      answer = -2
      
iv. x%=++y;
      answer = 0;

v. y-=++x;
      answer = -6
            
 
            
            
/*****************************
QUESTION 6
****************************/
 6a. 
      
#include <iostream>
#include <cmath>

using namespace std;

int main(){
  
  int num1;
  int num2;
  double num3 = 0.0;
  double num4 = 0.0;
  double sum = 0.0;
  double average = 0.0;
  double sumSquare = 0.0;

  cout << "Enter two integer and two double values" << endl;
  cin >> num1 >> num2 >> num3 >> num4;
  
  sum = num1 + num2 + num3 + num4;
  average = sum / 4;
  sumSquare = sum * sum;
  
  cout << "Sum = " << sum << endl;
  cout << "Average = " << average << endl;
  cout << "Square of sum = " << sumSquare << endl;
  
  return 0;
}

6b. VALID IDENTIFER  
    - myFees
    - Else
    - returns
    - CHAR
    
    INVALID IDENTIFIER
    - Student Name
    - public
    - #plate_number
    - 1stAttempt
    - Else
    - return
    - phone-Number
 
           
           
           
           
            
/*****************************
QUESTION 7
****************************/
 7b.
            
 // FIND THE AREA AND PERIMETER OF RECTANGLE USING C++ CLASS

#include <iostream>
#include <cmath>

using namespace std;

class AreaAndPerimeterOfRectangle
{ 
    public: 
    
    int length;
    int breadth;
    int perimeter;
    int areaOfRec;
      
    //Default Constructor 
    AreaAndPerimeterOfRectangle() 
    { 
        //cout << "Default Constructor will always be called" << endl;  
    } 
      
    //Parameterized Constructor 
    //Constructor to assign values to data members
    AreaAndPerimeterOfRectangle(int a,int b) 
    { 
        length = a;
        breadth = b;
        //cout << "Parametrized Constructor called" << endl; 
    } 
    
    // Method to find perimeter of rectangle
    void peri()
    {
        perimeter = 2 * (length + breadth);
        cout << "Perimeter of the rectangle is " << perimeter << endl; 
    }
    
    // Method to find area of triangle
    void area()
    {
        areaOfRec = length * breadth;
        cout << "Area of Recangle : "<< areaOfRec <<endl;
        
    }
}; 

// Test Driver
int main() { 
      
    int length;
    int breadth;
      
    cout<< "Enter Length and Breadth of Rectangle" << endl;
    cin >> length >> breadth;
      
    // areaObject will call Default Constructor 
    AreaAndPerimeterOfRectangle areaObject; 
      
    // Create an instance of the AreaAndPerimaterOfRectangle class and initiliaze your Constructor
    // Parameterized Constructor 
    AreaAndPerimeterOfRectangle areaObject2(length,breadth); 
    
    // Call perimater of rectangle
    areaObject2.peri(); 
    
    // Call area of rectangle
    areaObject2.area(); 
    
    return 0; 
}