I can't get my C$++$ code to do input validation on all values entered and I need it to$.$ I need it to reject a negative input for all entered.

#include

using namespace std;

int getArea$()\{$

int area;

do $\{$

cout $<<$ "Enter the square feet of floor space in the room: $"$;

cin $>>$ area;

if $($area $<0)\{$

cout $<<$ "Invalid input. Please enter a non$-$negative value.

$"$;

$\}$

$\}$ while $($area $<0)$;

return area;

$\}$

int main$()\{$

int numRooms, areaPerRoom, totalArea $=0$;

double carpetPricePerSqFt, totalCost, laborCost;

cout $<<$ "Enter the number of rooms to be carpeted: $"$;

cin $>>$ numRooms;

for $($int i $=1$; i $<=$ numRooms; $++$i$)\{$

cout $<<$ "Room $"<<$ i $<<"$:

$"$;

areaPerRoom $=$ getArea$()$;

totalArea $+=$ areaPerRoom;

$\}$

cout $<<$ "Enter the price of the carpet per square foot: $$"$;

cin $>>$ carpetPricePerSqFt;

$//$ Calculate labor cost

int laborHours $=$ totalArea $/50$;

laborCost $=$ laborHours $*6*30$;

$//$ Calculate total cost

double carpetCost $=$ totalArea $*$ carpetPricePerSqFt;

totalCost $=$ carpetCost $+$ laborCost;

$//$ Display the results

cout $<<"$

Area to be carpeted: $"<<$ totalArea $<<"$ square feet" $<<$ endl;

cout $<<$ "Cost of the carpet: $$"<<$ carpetCost $<<$ endl;

cout $<<$ "Cost of labor: $$"<<$ laborCost $<<$ endl;

cout $<<$ "Total cost to the customer: $$"<<$ totalCost $<<$ endl;

return $0$;

$\}$