# Write a Program to find the greatest number among the three numbers

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Vinay Khatri
Last updated on September 10, 2024

## Problem Statement

We have given 3 numbers ``` num_1 ``` , ``` num_2 ``` and ``` num_3 ``` , as input from the user and we need to write a script or program that print the greatest one.

For Example

Input

```num_1 = 20
num_2 = 30
num_3 = 40```

Output

`The greatest number is: 40`

## Solution

The problem is very simple and beginner level. To solve the problem we just need to check if the ``` num_1 ``` is greater or equal to than ``` num_2 ``` and ``` num_3 ``` . If yes we will print the ``` num_1 ``` is the greatest, if not we will check if ``` num_2 ``` is greater than or equal ``` num_1 ``` and num_3 if yes we will print that ``` num_2 ``` is the greatest. Even if ``` num_2 ``` is not the greatest we will simply print that num_3 is the greatest. To solve this problem we only require of...else statement.

### C Program to Find the Greatest Number among the three numbers

``````#include <stdio.h>

int main()
{
int num_1,num_2,num_3;
//input the first number
printf("Enter the first number: ");
scanf("%d", &num_1);

//input the second number
printf("Enter the second number: ");
scanf("%d", &num_2);

// input the third number
printf("Enter the third number: ");
scanf("%d",&num_3);

//if the number 1 is the greatest
if(num_1 >= num_2 && num_1>=num_3)
printf("The greatest number is: %d",num_1);

// if teh number 2 is the greatest
else if(num_2 >=num_1 && num_2>=num_3)
printf("The greatest number is: %d",num_2);

// if the number 3 is the greatest
else
printf("The greatest number is: %d" ,num_3);
return 0;
}``````

Output

``````Enter the first number: 12
Enter the second number: 45
Enter the third number: 15
The greatest number is: 45``````

### C++ Program to find the greatest number among the three numbers

``````#include<iostream>
using namespace std;
int main()
{
int num_1,num_2,num_3;

//input the first number
cout<<"Enter the first number: "; cin>>num_1;

//input the second number
cout<<"Enter the second number: "; cin>>num_2;

//input the third number
cout<<"Enter the third number: "; cin>>num_3;

//check if number 1 is the greatest
if(num_1 >= num_2 && num_1>=num_3)
cout<<"The greatest number is: "<<num_1;

//check if number 2 is the greatest
else if(num_2 >=num_1 && num_2>=num_3)
cout<<"The greatest number is: "<<num_2;

//if the number 3 is the greatest
else
cout<<"The greatest number is: " <<num_3;
return 0;
}``````

Output:

``````Enter the first number: 12
Enter the second number: 23
Enter the third number: 54
The greatest number is: 54``````

### Python Program to find the greatest number among the three numbers

``````# input the first number
num_1= int(input("Enter the first number: "))

# input the second number
num_2= int(input("Enter the second number: "))

# input the third number
num_3= int(input("Enter the third number: "))

# if the number 1 is the greatest
if num_1>=num_2  and num_1 >= num_3:
print("The greatest number is:", num_1)

# if the numer 2 is the greatest
elif num_2>=num_1  and num_2 >= num_2:
print("The greatest number is:", num_2)

# if the number 3 is the greatest
else:
print("The greatest number is:", num_3)``````

Output:

``````Enter the first number: 45
Enter the second number: 78
Enter the third number: 23
The greatest number is: 78``````

## Wrapping Up!

In this programming tutorial, we learned how to find out the greatest number among 3 numbers. The trick to solve this problem is lies behind the use of ``` if....else ``` statements with proper conditions. Here we only have 3 numbers which mean we can easily use the ``` if....else ``` statement and check for every number if the number is greater than or equal to the other two numbers.