### C# program to find the largest of three numbers:

In this *C# program*, we will learn how to find the largest of three numbers. The program will ask the user to enter these numbers one by one and then it will find the *largest* of three numbers and print it out.

We will learn two different ways to solve this problem. The *first one* will use one basic way to solve it by *comparing the numbers* and the other one will use one *system function* to find out the max of two.

### Method 1: By using simple comparison:

Letâ€™s solve it by using a simple comparison. Below is the algorithm for that:

- Get the numbers.
- Check the largest of
*first two*. - If
*first > second*, compare*first*with*third*and find the largest. - Else, compare
*second*with*third*and find the largest.

Below is the complete program:

```
using System;
namespace dotnet_sample
{
class Program
{
static void Main(string[] args)
{
//1
int first, second, third;
//2
Console.WriteLine("Enter the first number : ");
first = int.Parse(Console.ReadLine());
Console.WriteLine("Enter the second number : ");
second = int.Parse(Console.ReadLine());
Console.WriteLine("Enter the third number : ");
third = int.Parse(Console.ReadLine());
//3
if (first > second)
{
//4
if (first > third)
{
Console.WriteLine("largest number : " + first);
}
else
{
Console.WriteLine("largest number : " + third);
}
}
else
{
if (second > third)
{
Console.WriteLine("largest number : " + second);
}
else
{
Console.WriteLine("largest number : " + third);
}
}
}
}
}
```

### Explanation:

*The commented numbers in the above program denote the step numbers below :*

- Create three integer variables to store the user inputs.
- Ask the user to enter the numbers. Read and store these in the variables.
- Check if
*first > third*. If yes, then compare*first*with*third*and print out the largest number. Else, check*second*with*third*and print the largest.

### Sample Output:

```
Enter the first number :
10
Enter the second number :
5
Enter the third number :
4
largest number : 10
```

### Method 2: By using Math.max():

The above process takes a lot of lines and checks to find out the *max value*. Instead, we can also use *Math.max()* function that is already defined. *Math.max()* takes two parameters and returns the max. So, we can use it *two* times to find out the maximum of *three*.

```
using System;
namespace dotnet_sample
{
class Program
{
static void Main(string[] args)
{
int first, second, third;
Console.WriteLine("Enter the first number : ");
first = int.Parse(Console.ReadLine());
Console.WriteLine("Enter the second number : ");
second = int.Parse(Console.ReadLine());
Console.WriteLine("Enter the third number : ");
third = int.Parse(Console.ReadLine());
int maxValue = Math.Max(Math.Max(first,second),third);
Console.WriteLine("Largest value : "+maxValue);
}
}
}
```

As you can see here, we are finding the maximum of three numbers in just *one line* :)

If you run this program, it will give the same output.

C# find largest of three numbers