In this C programming tutorial, we will write a program to find the sum of even and odd numbers from 1 to n, where n is a positive integer entered by the user. This program demonstrates the use of loops, conditional statements, and arithmetic operations in C programming.

**Problem Statement:**

Write a C program to find the sum of even and odd numbers from 1 to n, where n is a positive integer entered by the user.

**Solution:**

To solve this problem, we will use a `for`

loop to iterate over the numbers from 1 to n. Inside the loop, we will use an `if`

statement to check whether the current number is even or odd, and we will update the sum of even and odd numbers accordingly. Here’s the code for our solution:

#include <stdio.h> int main() { int n, i, even_sum = 0, odd_sum = 0; printf("Enter a positive integer: "); scanf("%d", &n); for(i = 1; i <= n; i++) { if(i % 2 == 0) { even_sum += i; } else { odd_sum += i; } } printf("Sum of even numbers from 1 to %d is %d\n", n, even_sum); printf("Sum of odd numbers from 1 to %d is %d\n", n, odd_sum); return 0; }

**Output**

- The
`stdio.h`

header file is included for standard input/output functions. - The
`main()`

function is declared as the entry point of the program. - The
`start`

,`end`

,`even_sum`

, and`odd_sum`

variables are declared.`even_sum`

and`odd_sum`

are initialized to zero. - The user is prompted to enter the starting number using
`printf()`

function. - The user input is read and stored in the
`start`

variable using`scanf()`

function. - The user is prompted to enter the ending number using
`printf()`

function. - The user input is read and stored in the
`end`

variable using`scanf()`

function. - A
`for`

loop is used to iterate through the numbers in the range from`start`

to`end`

. - An
`if-else`

statement is used to determine whether each number is even or odd. - If the number is even (i.e., the remainder when dividing by 2 is 0), the
`even_sum`

variable is updated to include the number. - If the number is odd (i.e., the remainder when dividing by 2 is 1), the
`odd_sum`

variable is updated to include the number. - Once the loop is complete, two
`printf()`

statements are called to display the sum of even and odd numbers in the given range. - The
`main()`

function returns 0, which indicates that the program has executed successfully.

**Explanation:**

The program begins by including the `stdio.h`

header file, which provides access to standard input/output functions. The `main()`

function is then declared as the entry point of the program, and the `start`

, `end`

, `even_sum`

, and `odd_sum`

variables are declared.

Next, the user is prompted to enter the starting number and the ending number using the `printf()`

function. The `scanf()`

function is then used to read the user input and store it in the `start`

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