C Program to Find Greatest Number Among Three Numbers

FIND GREATEST NUMBER AMONG THREE NUMBERS

In this program we learn how to find greatest number among three number provided by user using C.

Example:

 Input : A = 6, B = 9, C = 11
 Output: Greatest Number = 11

 Input : A = 456, B = 129, C = 99
 Output: Greatest Number = 456

Here  we learn , to find  greatest number among three numbers by using if, if-else, nested if-else and Ternary operator in C.

Algorithm to find  greatest number among three numbers:

Step 1: Start
Step 2: Read three numbers as A, B and C.
Step 3: Check if A is greater than B.
   Step 3.1: If true, then check if A is greater than C.
      Step 3.1.1: If true, then print 'A' is largest number.
      Step 3.1.2: If false, then print 'C' is largest number.

   Step 3.2: If false, then check if B is greater than C.
      Step 3.2.1: If true, then print 'B' is largest number.
      Step 3.2.2: If false, then print 'C' is largest number.
Step 4: End

FlowChart to find  greatest number among three numbers:

Below the example  the C program to find  greatest number among three numbers.

Example 1:  Using only if statement to find greatest number among three numbers.

// Find greatest in 3 numbers
#include <stdio.h>
#include <conio.h>
void main()
{
	int a,b,c;
	clrscr();
	printf("\n Enter  three numbers : ");
	scanf("%d%d%d",&a,&b,&c);
	if(a>b && a>c)
    	     printf("\n The greatest number : %d",a);
        if(b>a && b>c)
	     printf("\n The greatest number : %d",b);
        if(c>a && c>b)
	     printf("\n The greatest number : %d",c);
	getch();
}

OUTPUT:

Enter three numbers:  44  22 77
The greatest number : 77

Example 2:  Using if-else statement to find greatest number among three numbers.

// Find greatest in 3 numbers
#include <stdio.h>
#include <conio.h>
void main()
{
	int a,b,c;
	clrscr();
	printf("\n Enter  three numbers : ");
	scanf("%d%d%d",&a,&b,&c);
	if(a>b)
        {
    	    if(a>c)
		printf("\n The greatest number : %d",a);
            else
		printf("\n The greatest number : %d",a);
        }
        else
        {
	    if(b>c)
        	printf("\n The greatest number : %d",b);
	    else
		printf("\n The greatest number : %d",c);
        }
	getch();
}

OUTPUT:

Enter three numbers:  14 2 7
The greatest number : 14

Example 3:  Using neasted if-else statement to find greatest number among three numbers.

// Find greatest in 3 numbers
#include <stdio.h>
#include <conio.h>
void main()
{
	int a,b,c;
	clrscr();
	printf("\n Enter  three numbers : ");
	scanf("%d%d%d",&a,&b,&c);
	if(a>b && a>c)
    	     printf("\n The greatest number : %d",a);
        else if(b>a && b>c)
	     printf("\n The greatest number : %d",b);
        else
	     printf("\n The greatest number : %d",c);
	getch();
}

OUTPUT:

Enter three numbers:  25 122 98
The greatest number : 122

Example 4:  Using Ternary operator to find greatest number among three numbers.

// Find greatest in 3 numbers
#include <stdio.h>
#include <conio.h>
void main()
{
	int a,b,c,greatest;
	clrscr();
	printf("\n Enter  three numbers : ");
	scanf("%d%d%d",&a,&b,&c);
        greatest = a > b ? (a>c ? a:c) : (b>c ? b:c);
	printf("\n The greatest number : %d",greatest);
	getch();
}

OUTPUT:

Enter three numbers:  10 8 5
The greatest number : 10