Write a program that ask user to enter two numbers, calculate and display their sum, difference and product. Calculate each of above using different user defined functions.

 Here's a program in C++ that asks the user to enter two numbers, calculates their sum, difference, and product using user-defined functions, and then displays the results:

#include <iostream>

using namespace std;

int sum(int a, int b) {

    return a + b;

}

int difference(int a, int b) {

    return a - b;

}

int product(int a, int b) {

    return a * b;

}

int main() {

    int num1, num2;

    cout << "Enter the first number: ";

    cin >> num1;

    cout << "Enter the second number: ";

    cin >> num2;

    int result_sum = sum(num1, num2);

    int result_diff = difference(num1, num2);

    int result_prod = product(num1, num2);

    cout << "The sum of the numbers is: " << result_sum << endl;

    cout << "The difference of the numbers is: " << result_diff << endl;

    cout << "The product of the numbers is: " << result_prod << endl;

    return 0;

}

In this program, we define three user-defined functions named sum, difference, and product, which take two arguments a and b, and return the sum, difference, and product of the two numbers respectively.

int sum(int a, int b) {

    return a + b;

}

int difference(int a, int b) {

    return a - b;

}

int product(int a, int b) {

    return a * b;

}

In the main function, we prompt the user to enter two numbers, and then read them in using the cin statement. We then call each of the user-defined functions to calculate the sum, difference, and product of the two numbers, and store the results in separate variables.

int num1, num2;

cout << "Enter the first number: ";

cin >> num1;

cout << "Enter the second number: ";

cin >> num2;

int result_sum = sum(num1, num2);

int result_diff = difference(num1, num2);

int result_prod = product(num1, num2);

Finally, we display the results using cout statements.

cout << "The sum of the numbers is: " << result_sum << endl;

cout << "The difference of the numbers is: " << result_diff << endl;

cout << "The product of the numbers is: " << result_prod << endl;

When the program runs, it will output something like this:

Enter the first number: 10

Enter the second number: 5

The sum of the numbers is: 15

The difference of the numbers is: 5

The product of the numbers is: 50