Need help with my program

#include

#include

#include

#include

#include

$//$ Function to compute factorial

int factorial$($int n$)\{$

if $($n $==0||$ n $==1)$

return $1$;

else

return n $*$ factorial$($n $-1)$;

$\}$

$//$ Function to check if a number is prime

int isPrime$($int num$)\{$

if $($num

return $0$;

for $($int i $=2$; i $*$ i num; i$++)\{$

if $($num $\%$ i $==0)$

return $0$;

$\}$

return $1$;

$\}$

int main$()\{$

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

int n;

$//$ Prompt user for the number of child processes to create

printf$("$Enter the number of child processes to create $($less than $5)$: $")$;

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

$//$ Validate input

if $($n $<mtext\; id="EditorElement\_838566"></mtext><mn\; id="EditorElement\_838567">1</mn><mtext\; id="EditorElement\_838568"></mtext><mi\; id="EditorElement\_838569">|</mi><mi\; id="EditorElement\_838570">|</mi>$ n $>4)\{$

printf$("$Invalid input. Please enter a number between $1$ and $4.$

$")$;

return $1$;

$\}$

$//$ Display initial message

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

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

$//$ Create child processes

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

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

if $($child$\_$pid $<mtext\; id="EditorElement\_838911"></mtext><mn\; id="EditorElement\_838912">0</mn><mi\; id="EditorElement\_838913">)</mi><mtext\; id="EditorElement\_838914"></mtext><mi\; id="EditorElement\_838915">\{</mi>$

perror$("$Fork failed"$)$;

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

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

$//$ This code will be executed by the child process

$//$ Print child's identifier $($PID$)$ and the task it is performing

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

$",$ i $+1,$ getpid$())$;

$//$ Perform different tasks based on child number

switch $($i$)\{$

case $0$:

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

$",$ i $+1,$ getpid$())$;

printf$("$Child $\%$d $($PID: $\%$d$)$ completed its task. Result: $\%$d

$",$ i $+1,$ getpid$(),$ factorial$(5))$;

break;

case $1$:

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

$",$ i $+1,$ getpid$())$;

printf$("$Child $\%$d $($PID: $\%$d$)$ completed its task. Result: $",$ i $+1,$ getpid$())$;

for $($int j $=2$; j ; j$++)\{$

if $($isPrime$($j$))$

printf$("\%$d $",$ j$)$;

$\}$

printf$("$

$")$;

break;

case $2$:

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

$",$ i $+1,$ getpid$())$;

printf$("$Child $\%$d $($PID: $\%$d$)$ completed its task. Result: Custom task completed.

$",$ i $+1,$ getpid$())$;

break;

$//$ Add more cases for additional child processes if needed

$\}$

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

$\}$

$\}$

$//$ This code will be executed by the parent process

$//$ Wait for all child processes to finish

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

wait$($NULL$)$;

$\}$

printf$("$All child processes have completed. Parent $($PID: $\%$d$)$ is displaying the final message.

$",$ getpid$())$;

return $0$;

$\}$