# C program to print ODD numbers from 1 to N using while loop

This is an example of while loop - In this C program, we are going to learn how can we print all ODD numbers from given range (1 to N) using while loop?
Submitted by Manju Tomar, on March 10, 2018

Given a range (value of N) and we have to print all ODD numbers from 1 to N using while loop.

Example:

```    Input:
Enter value of N: 10

Output:
ODD Numbers from 1 to 10:
1 3 5 7 9
```

Logic:

• There are two variables declared in the program 1) number as a loop counter and 2) n to store the limit.
• Reading value of n by the user.
• Initialising loop counter (number) by 1 as initial value number =1
• Using while loop by checking the condition number<=n (value of number is less than or equal to n) - this will execute the loop until the value of number is less than or equal to n.
• Then, within the loop, we are checking the condition to check whether number is ODD or not, the condition is (number%2 != 0) - it returns true if number is not divisible by 2.

## Program to print ODD numbers from 1 to N using while loop

```#include <stdio.h>

int main()
{
//loop counter declaration
int number;
//variable to store limit /N
int n;

//from where we want to print the numbers
number=1;

//input value of N
printf("Enter the value of N: ");
scanf("%d",&n);

//print statement
printf("Odd Numbers from 1 to %d:\n",n);

//while loop, that will print numbers
while(number<=n)
{
//Here is the condition to check ODD number
if(number%2 != 0)
printf("%d ",number);

// increasing loop counter by 1
number++;
}

return 0;
}
```

Output

```Run(1)
Enter the value of N: 10
Odd Numbers from 1 to 10:
1 3 5 7 9

Run(2)
Enter the value of N: 100
Odd Numbers from 1 to 100:
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31
33 35 37 39 41 43 45 47 49 51 53 55 57 59
61 63 65 67 69 71 73 75 77 79 81 83 85 87
89 91 93 95 97 99
```

### Another way to print ODD numbers from 1 to N

Since, we know that ODD numbers starts from 1 and ODD numbers are those numbers which are not divisible by 2. So, we can run a loop from 1 to N by increasing the value of loop counter by 2.

Consider the given code...

```//initialising the number by 1
number=1;
//print statement
printf("Odd Numbers from 1 to %d:\n",n);

//while loop, that will print numbers
while(number<=n)
{
//print the number
printf("%d ",number);
//increase the value of number by 2
number+=2;
}
```