Question

 Write a function, which accept three integer values as arguments find the largest of three and then return the largest value to main program. Write a main program which will call the function by passing three integer values and print the value returned by the function.?

Answer 1

1. First we create a function that takes the value as a parameter.

void findLargestNumber(int, int, int); // Prototype
void findLargestNumber(int num1, int num2, int num3)
{
}

2. After creating the function now we implement the logic to compare given value/integers. The Logic is given below

   if (num1 == 0 || num2 == 0 || num3 == 0)
    {
        cout << "No one must be zero";
    }
    else if (num1 > num2 && num1 > num3)
    {
        cout << num1 << " is largest number";
    }
    else if (num2 > num1 && num2 > num3)
    {
        cout << num2 << " is largest number";
    }
    else if (num3 > num1 && num3 > num2)
    {
        cout << num3 << " is largest number";
    }

3. Now we implement this into our function.

void findLargestNumber(int num1, int num2, int num3)
{
    if (num1 == 0 || num2 == 0 || num3 == 0)
    {
        cout << "No one must be zero";
    }
    else if (num1 > num2 && num1 > num3)
    {
        cout << num1 << " is largest number";
    }
    else if (num2 > num1 && num2 > num3)
    {
        cout << num2 << " is largest number";
    }
    else if (num3 > num1 && num3 > num2)
    {
        cout << num3 << " is largest number";
    }
}

4. After that now we call this function in our main program and pass the value through the user.

// Main Function
int main()
{
    int firstNumber, secondNumber, thirdNumber;
    cout << "Enter First Number: ";
    cin >> firstNumber;
    cout << "Enter Second Number: ";
    cin >> secondNumber;
    cout << "Enter Third Number: ";
    cin >> thirdNumber;
    findLargestNumber(firstNumber, secondNumber, thirdNumber);
    getch();
}
// Our Logical Function which compare integers
void findLargestNumber(int num1, int num2, int num3)
{
    if (num1 == 0 || num2 == 0 || num3 == 0)
    {
        cout << "No one must be zero";
    }
    else if (num1 > num2 && num1 > num3)
    {
        cout << num1 << " is largest number";
    }
    else if (num2 > num1 && num2 > num3)
    {
        cout << num2 << " is largest number";
    }
    else if (num3 > num1 && num3 > num2)
    {
        cout << num3 << " is largest number";
    }
}

5. That's all and the final program looks like this.

#include <iostream>
#include <conio.h>
using namespace std;
void findLargestNumber(int, int, int); // Prototype
// Main Function
int main()
{
    int firstNumber, secondNumber, thirdNumber;
    cout << "Enter First Number: ";
    cin >> firstNumber;
    cout << "Enter Second Number: ";
    cin >> secondNumber;
    cout << "Enter Third Number: ";
    cin >> thirdNumber;
    findLargestNumber(firstNumber, secondNumber, thirdNumber);
    getch();
}
// Our logical function
void findLargestNumber(int num1, int num2, int num3)
{
    if (num1 == 0 || num2 == 0 || num3 == 0)
    {
        cout << "No one must be zero";
    }
    else if (num1 > num2 && num1 > num3)
    {
        cout << num1 << " is largest number";
    }
    else if (num2 > num1 && num2 > num3)
    {
        cout << num2 << " is largest number";
    }
    else if (num3 > num1 && num3 > num2)
    {
        cout << num3 << " is largest number";
    }
}

#include <iostream>
#include <conio.h>
using namespace std;
void findLargestNumber(int, int, int);
int main()
{
    int firstNumber, secondNumber, thirdNumber;
    cout << "Enter First Number: ";
    cin >> firstNumber;
    cout << "Enter Second Number: ";
    cin >> secondNumber;
    cout << "Enter Third Number: ";
    cin >> thirdNumber;
    findLargestNumber(firstNumber, secondNumber, thirdNumber);
    getch();
}
void findLargestNumber(int num1, int num2, int num3)
{
    if (num1 == 0 || num2 == 0 || num3 == 0)
    {
        cout << "No one must be zero";
    }
    else if (num1 > num2 && num1 > num3)
    {
        cout << num1 << " is largest number";
    }
    else if (num2 > num1 && num2 > num3)
    {
        cout << num2 << " is largest number";
    }
    else if (num3 > num1 && num3 > num2)
    {
        cout << num3 << " is largest number";
    }
}