Howdy readers, today you will learn **how to write a C++ program to find the largest of three numbers using functions**.

The below program prompts the user to enter three numbers, then it computes the largest among them using a **user-defined function**.

The** user-defined function** uses comparison operators to find the largest number in the below program.

So, without any delay, letâ€™s begin this tutorial.

**C++ Program to Find Largest of Three Numbers Using Functions**

**C++ Program**

// C++ Program to Find Largest of Three Numbers Using Functions #include <iostream> using namespace std; // User-defined function int largestNumber(int a, int b, int c){ int max; if (a >= b && a >= c){ max = a; } else if (b >= a && b >= c){ max = b; } else{ max = c; } return max; } int main(){ int num1, num2, num3, largest; // Taking input cout << "Enter the first number: "; cin >> num1; cout << "Enter the second number: "; cin >> num2; cout << "Enter the third number: "; cin >> num3; // Calling out function largest = largestNumber(num1, num2, num3); // Display result cout << "Largest number is: " << largest << endl; return 0; }

**Output**

Enter the first number: 18 Enter the second number: 30 Enter the third number: 27 Largest number is: 30

**Explanation**

int largestNumber(int a, int b, int c){ int max; if (a >= b && a >= c){ max = a; } else if (b >= a && b >= c){ max = b; } else{ max = c; } return max; }

In this program, we have defined a function named ** largestNumber** which passes three numbers as arguments and

**returns**the greatest of them.

// Calling out function largest = largestNumber(num1, num2, num3);

Then, we call out the custom function in the **main** function. This gives us the desired result. We store the largest number in the ** largest** named variable.

cout << "Largest number is: " << largest << endl;

The largest number among the three is displayed on the screen using the ** cout** statement.

**Conclusion**

Today you learned **how to write a C++ program to find the largest of three numbers using a function**.

If you have any doubts regarding the tutorial, comment down your queries in the comment section.

Thanks for reading.

Happy Coding!!

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**C++ Program to Find Largest of Two Numbers****C++ Program to Find Largest of Three Numbers****C++ Program to Find the Volume of a Cylinder****C++ Program to Find Factorial of a Number****C++ Program to Multiply Two Numbers Using Function**