Q3: Write a C++ program to read five numbers, find their sum, and print the numbers in reverse order.

#include <iostream>
using namespace std;

int main()
{
    int sum=0;
    int number [5];

    cout<<"enter the five number : "<<endl;

    for (int i = 0; i < 5; i++)
    {
        cout<<" number "<<i+1<<" : ";
        cin>>number[i];
        sum += number[i];
    }
    cout<<" the sum "<<sum<<endl;
    cout<<" number in reverse : "<<endl;
    for (int i = 4; i>=0; i--)
    {
        cout<< number[i]<<", ";
    }

    return 0;
}

Q4: Write a C++ program to find the sum and average of six numbers.

#include <iostream>
using namespace std;

int main()
{
    float sum=0;
    float average;
    float number [6];
    cout<< " enter the six number : "<<endl;
    for (int i = 0; i < 6; i++)
    {
        cout<<" number "<<i+1<<" : ";
        cin>>number[i];
        sum += number[i];
        average = sum/6;
    }
    cout<<" the sum "<<sum<<endl;
    cout<<" the average "<<average<<endl;
    return 0;
}

Q5: Write a C++ program to print the sequence of numbers (10, 11, 12 … 30). Use while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 10;
while ( a <= 30)
{
cout<<a<<", ";
a++;
}
return 0;
}

Q6: Write a C++ program to print the sequence of odd numbers from (11 - 29). Use while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 11;
while ( a <= 29)
{
cout<<a<<", ";
a += 2;
}
return 0;
}

Q7: Write a C++ program to print the sequence of even numbers from (10 - 30). Use while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 10;
while ( a <= 30)
{
cout<<a<<", ";
a += 2;
}
return 0;
}

Q8: Write a C++ program to print the sequence of numbers (15, 16, 17 … 30). Use do while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 15;
do
{
cout<<a<<", ";
a++;
}
while ( a < 30);
cout<<a<<", ";
return 0;
}

Q9: Write a C++ program to print the sequence of odd numbers from (11 - 29). Use do while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 11;
do
{
cout<<a<<", ";
a += 2;
}
while ( a < 29);
cout<<a<<", ";
return 0;
}

Q10: Write a C++ program to print the sequence of even numbers from (10 - 30). Use do while loop statement.

#include <iostream>
using namespace std;
int main ()
{
int a = 10;
do
{
cout<<a<<", ";
a += 2;
}
while ( a < 30);
cout<<a<<", ";
return 0;
}

Q11: Write a C++ program that takes two integers as input and checks if they are equal, greater than, or less than each other

#include <iostream>
using namespace std;
int main ()
{
int a, b;
cout<<"enter the value of a : ";
cin>>a;
cout<<"enter the value of b : ";
cin>>b;

if ( a == b )
{
cout<<" a equal b "<<endl;
}
else if ( a > b)
{
cout<<" a is greater than b "<<endl;
}
else if ( a < b )
{
cout<<" a is less than b "<<endl;
}
return 0;
}

Q12: Create a C++ program that determines whether a given year is a leap year or not. Provide appropriate messages based on the result.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    int year; 
 
    cout << "Enter a year: "; 
    cin >> year; 
 
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))  
 { 
        cout << year << " is a leap year." << endl; 
    }  
 else  
 { 
        cout << year << " is not a leap year." << endl; 
    } 
 
    return 0; 
}

Q13: Implement a C++ program that takes a student's percentage as input and assigns a grade according to the following criteria:
90% and above: A
80-89%: B
70-79%: C
Below 70%: F

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    int grade;
    cout<<" enter your grade ";
    cin>>grade;
    if ( grade > 90 )
    {
    cout<<" your grade is : A "<<endl;
    }
    else if ( grade > 80 )
    {
    cout<<" your grade is : B "<<endl;
    }
    else if ( grade > 70 )
    {
    cout<<" your grade is : C "<<endl;
    }
    else
    {
    cout<<" your grade is : F "<<endl;
    } 
    return 0; 
}

Q14: Write a C++ program to determine if a given number is positive, negative, or zero. Use appropriate conditional statements.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    int num;
    cout<<" enter the number ";
    cin>>num;
    if ( num > 0 )
    {
    cout<<" the number is positive "<<endl;
    }
    else if ( num < 0)
    {
    cout<<" the number is negative "<<endl;
    }
    
    else
    {
    cout<<" the number is zero "<<endl;
    } 
    return 0; 
}

Q15: Develop a simple C++ calculator program with a menu that performs addition, subtraction, multiplication, and division based on the user's choice.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    float num1, num2, result;
    char op;
    cout<<" enter the number1 : ";
    cin>>num1;
    cout<<" enter operator (+, -, *, /) : ";
    cin>>op;
    cout<<" enter the number2 : ";
    cin>>num2;
    switch (op)
    {
    case '+':
    result = num1 + num2;
    break;
    case '-':
    result = num1 - num2;
    break;
    case '*':
    result = num1 * num2;
    break;
    case '/':
    if ( num2 != 0)
    {
    result = num1 / num2;
    }
    else
    {
    cout<<" error "<<endl;
    return 1;
    }
    break;
    default:
    cout<<" error "<<endl;
    return 1;
    }
    
    cout<<result<<endl;
    
    return 0;
}

Q16: Create a C++ program that takes a character as input and determines whether it is a vowel, consonant.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    char character; 
 
    cout << "Enter a character: "; 
    cin >> character; 
 
    if ((character >= 'a' && character <= 'z') || (character >= 'A' && character <= 'Z'))  
 { 
        switch (character)  
  { 
            case 'a': 
            case 'e': 
            case 'i': 
            case 'o': 
            case 'u': 
            case 'A': 
            case 'E': 
            case 'I': 
            case 'O': 
            case 'U': 
                cout << character << " is a vowel." << endl; 
                break; 
            default: 
                cout << character << " is a consonant." << endl; 
        } 
    }  
 else  
 { 
        cout << "Invalid input. Please enter a valid alphabet character." << endl; 
    } 
 
    return 0; 
}

Q17: Write a C++ program that classifies a person into different age groups: child (0-12), teenager (13-19), adult (20-59), or senior (60 and above).

#include <iostream>
using namespace std;
int main()
{
int age;
cout<<" enter your age : ";
cin>>age;
if( age <= 12 )
{
cout<<"your a child"<<endl;
}
else if ( age <=19 )
{
cout<<"your a teenager"<<endl;
}
else if ( age <= 59 )
{
cout<<"your a adult"<<endl;
}
else if ( age >= 60 )
{
cout<<"your a senior"<<endl;
}
return 0;
}

Q18: Implement a C++ program that converts temperatures between Celsius and Fahrenheit. Ask the user for the temperature and the unit, then perform the conversion based on the input. Hint:
(Temperature in degrees Fahrenheit (°F) = (Temperature in degrees Celsius (°C) * 9/5) + 32)

#include <iostream>
using namespace std;
int main() {
float c, f;
cout << " value ";
cin >> c;
f = ( c * 9/5 ) + 32;
cout << " in F the temp is :" << f <<endl;
    return 0;
}

Q19: Create a C++ program that takes two integers as input and checks whether the first number is divisible by the second one. Provide appropriate messages based on the result.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    int num1, num2; 
 
    cout << "Enter the first number: "; 
    cin >> num1; 
 
    cout << "Enter the second number: "; 
    cin >> num2; 
 
    if (num2 != 0)  
 { 
        if (num1 % num2 == 0)  
  { 
            cout << num1 << " is divisible by " << num2 << endl; 
        }  
  else  
  { 
            cout << num1 << " is not divisible by " << num2 << endl; 
        } 
    }  
 else  
 { 
        cout << "Error: Division by zero is not allowed." << endl; 
    } 
 
    return 0; 
}

Q20: Write a C++ program that takes three numbers as input and determines the largest among them using conditional statements

#include <iostream> 
using namespace std; 
 
int main() { 
    double num1, num2, num3; 
 
    cout << "Enter num1 : "; 
    cin >> num1; 
 
    cout << "Enter num2 : "; 
    cin >> num2; 
 
    cout << "Enter num3 : "; 
    cin >> num3; 
 
    if (num1 >= num2 && num1 >= num3) { 
        cout << "The largest number is : " << num1 << endl; 
    }  
 else if (num2 >= num1 && num2 >= num3)  
 { 
        cout << "The largest number is : " << num2 << endl; 
    }  
 else  
 { 
        cout << "The largest number is : " << num3 << endl; 
    } 
 
    return 0; 
}

Q21: Create a C++ program that takes three angles as input and classifies the triangle based on the angle values (acute, obtuse, or right-angled). determines the largest among them using conditional statements

#include <iostream> 
using namespace std; 
 
int main()  
{ 
    int angle1, angle2, angle3; 
 
    cout << "Enter the first angle: "; 
    cin >> angle1; 
 
    cout << "Enter the second angle: "; 
    cin >> angle2; 
 
    cout << "Enter the third angle: "; 
    cin >> angle3; 
 
    if (angle1 + angle2 + angle3 == 180)  
 { 
        if (angle1 < 90 && angle2 < 90 && angle3 < 90)  
  { 
            cout << "The triangle is acute-angled." << endl; 
        }  
  else if (angle1 == 90 || angle2 == 90 || angle3 == 90)  
  { 
            cout << "The triangle is right-angled." << endl; 
        } 
   else  
  { 
            cout << "The triangle is obtuse-angled." << endl; 
        } 
    }  
 else  
 { 
        cout << "Invalid input: The angles do not form a triangle." << endl; 
    } 
 
    return 0; 
}

Q22: Write a C++ program that calculates the total cost after applying a discount based on the purchase amount. For example, provide a 10% discount if the purchase amount is above $100.

#include <iostream> 
using namespace std; 
 
int main()  
{ 
int purchaseamount, discount, totalcost;
cout<<" enter the purchaseamount: ";
cin>>purchaseamount;
if ( purchaseamount > 100)
{
discount = 0.10 * purchaseamount;
}
else
{
discount = 0;
}
totalcost = purchaseamount - discount;

cout<< "Discount applied: $"<<discount<<endl;
cout<< "Total cost after discount: $"<<totalcost<<endl;

return 0; 
}