Calculation in parent and child process using fork()

Write a program to find sum of even numbers in parent process and sum of odd numbers in child process.

**Examples:**

Input : 1, 2, 3, 4, 5 Output : Parent process Sum of even no. is 6 Child process Sum of odd no. is 10

**Explanation: **Here, we had used fork() function to create two processes one child and one parent process.

- For child process fork()
**returns 0**so we can calculate sum of all odd numbers in child process. - fork() returns value
**greater than 0**for parent process so we can calculate sum - for all even numbers there by just simply checking the value returned by fork().

`// C++ program to demonstrate calculation in parent and` `// child processes using fork()` `#include <iostream>` `#include <unistd.h>` `using` `namespace` `std;` ` ` `// Driver code` `int` `main()` `{` ` ` `int` `a[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };` ` ` `int` `sumOdd = 0, sumEven = 0, n, i;` ` ` `n = fork();` ` ` ` ` `// Checking if n is not 0` ` ` `if` `(n > 0) {` ` ` `for` `(i = 0; i < 10; i++) {` ` ` `if` `(a[i] % 2 == 0)` ` ` `sumEven = sumEven + a[i];` ` ` `}` ` ` `cout << ` `"Parent process \n"` `;` ` ` `cout << ` `"Sum of even no. is "` `<< sumEven << endl;` ` ` `}` ` ` ` ` `// If n is 0 i.e. we are in child process` ` ` `else` `{` ` ` `for` `(i = 0; i < 10; i++) {` ` ` `if` `(a[i] % 2 != 0)` ` ` `sumOdd = sumOdd + a[i];` ` ` `}` ` ` `cout << ` `"Child process \n"` `;` ` ` `cout << ` `"\nSum of odd no. is "` `<< sumOdd << endl;` ` ` `}` ` ` `return` `0;` `}` |

Output:

Parent process Sum of even no. is 30 Child process Sum of odd no. is 25

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