Write a C program that simulates a parallel task execution scenario using process forking. The program should create a specified number of child processes, each performing a unique task. The parent process should wait for all child processes to complete before displaying the final result.

Requirements:

Your program should take an integer input n from the user, where n represents the number of child processes to be created. n should be less than $5.$

Each child process should perform a different task, such as computing the factorial of a number, finding prime numbers in a range, or any computationally intensive operation.

The parent process should display a message before creating $($forking$)$ the child processes.

Each child process should print its own identifier $($PID$)$ and the task it is performing.

After completing their tasks, each child process should print a completion message.

The parent process should wait for all child processes to finish before displaying a final message.

Additional Considerations:

Use the fork$()$ system call to create child processes.

You may use other relevant system calls or functions as needed $($e$.$g$.,$ wait$(),$ exit$()).$

Ensure proper error handling for system calls.

Design the code to guarantee the creation of exactly n children, ensuring that each child executes its intended task. Properly manage the process creation to avoid any unintended duplication or omission of child processes.

#include

#include

#include

#include

$//$ Function prototypes for child tasks

void task$1()$;

void task$2()$;

void task$3()$;

int main$()\{$

int n;

printf$("$Enter the number of child processes to create: $")$;

scanf$("\%$d$",$ &n$)$;

if $($n $<1||$ n $>5)\{$

printf$("$Number of child processes must be between $1$ and $5.$

$")$;

exit$($EXIT$\_$FAILURE$)$;

$\}$

printf$("$Parent process $($PID: $\%$d$)$ is creating $\%$d child processes.

$",$ getpid$(),$ n$)$;

$//$ Forking child processes

for $($int i $=0$; i $<$ n; $++$i$)\{$

pid$\_$t pid $=$ fork$()$;

if $($pid $==-1)\{$

$//$ Error handling for fork

perror$("$fork$")$;

exit$($EXIT$\_$FAILURE$)$;

$\}$ else if $($pid $==0)\{$

$//$ Child process

$//$ Perform task based on child process ID

switch $($i$)\{$

case $0$:

task$1()$;

break;

case $1$:

task$2()$;

break;

case $2$:

task$3()$;

break;

$//$ Add more cases for additional tasks if needed

$\}$

exit$($EXIT$\_$SUCCESS$)$;

$\}$

$\}$

$//$ Parent process waits for all child processes to complete

int status;

pid$\_$t child$\_$pid;

while $(($child$\_$pid $=$ wait$($&status$))>0)\{$

printf$("$Child process with PID $\%$d completed.

$",$ child$\_$pid$)$;

$\}$

$//$ Final message from parent

printf$("$All child processes have completed.

$")$;

return $0$;

$\}$

$//$ Sample task functions $($replace with your own tasks$)$

void task$1()\{$

printf$("$Child process $($PID: $\%$d$)$ is computing the factorial of $5.$

$",$ getpid$())$;

$//$ Perform factorial calculation here

$\}$

void task$2()\{$

printf$("$Child process $($PID: $\%$d$)$ is finding prime numbers up to $20.$

$",$ getpid$())$;

$//$ Find prime numbers here

$\}$

void task$3()\{$

printf$("$Child process $($PID: $\%$d$)$ is performing a custom task.

$",$ getpid$())$;

$//$ Custom task here

$\}$

ample output:

$ $./$parallel$\_$execution

Enter the number of child processes to create: $3$

Parent process $($PID: $1234)$ is creating $3$ child processes.

Child $1($PID: $1235)$ is computing the factorial of $5.$

Child $2($PID: $1236)$ is finding prime numbers up to $20.$

Child $3($PID: $1237)$ is performing a custom task.

Child $1($PID: $1235)$ completed its task. Result: $120$

Child $2($PID: $1236)$ completed its task. Result: $235711131719$

Child $3($PID: $1237)$ completed its task. Result: Custom task completed.

All child processes have completed. Parent $($PID: $1234)$ is displaying the final message.