C++, Problem 7 - Fish Tank

# include <iostream>
using namespace std;
#include <iomanip>

int main()
{
    int lenght;
    do
    {
        cin.clear();
        cin >> lenght;
    }
    while (cin.bad() || lenght <10 || lenght > 500);
    int width;
    {
        cin.clear();
        cin >> width;
    }
    while (cin.bad() || width < 10 || width > 300);
    int height;
    do
    {
        cin.clear();
        cin >> height;
    }
    while (cin.bad() || height < 10 || height > 500);
    double percent;
    do
    {
    cin.clear(); cin >> percent;
    }
    while (cin.bad() || percent < 0 || percent > 100);
    double capacity = (lenght * width * height) * 0.001;
    double free = (capacity - (capacity * percent / 100));
    cout << fixed << setprecision(3) << free << endl;
    return 0;
 }