#include <iostream>
using namespace std;

int main()
{
    // Get the cost of soil.
    std::string Soil;
    std::cout << "What does the soil cost? " <<std::endl;
    std::cin >> Soil;

    // Get the cost of flower seeds.
    std::string Flower;
    std::cout << "What do the flower seeds cost? " <<std::endl;
    std::cin >> Flower;

    // Get the cost of the fence.
    std::string Fence;
    std::cout << "What does the fence cost? " <<std::endl;
    std::cin >> Fence;

    // Calculate the total cost.
    std::string total;
    std::cout total = Soil + Flower + Fence;

    // Display the total cost
    std::cout << "The total cost is $" << total;
    std::cout << "." << std::endl;

    return 0;
}

int main()
{
    // Get the cost of soil.
    double Soil;
    std::cout << "What does the soil cost? " <<std::endl;
    std::cin >> Soil;

    // Get the cost of flower seeds.
    double Flower;
    std::cout << "What do the flower seeds cost? " <<std::endl;
    std::cin >> Flower;

    // Get the cost of the fence.
    double Fence;
    std::cout << "What does the fence cost? " <<std::endl;
    std::cin >> Fence;

    // Calculate the total cost.
    double total =Soil + Flower + Fence;

    // Display the total cost
    std::cout << "The total cost is $" << total;
    std::cout << "." << std::endl;

    return 0;
}

#include <iostream>
using namespace std;

int main()
{
int soil, flower, fence, total;

// Get the cost of soil.
std::cout << "What does the soil cost? " <<std::endl;
std::cin >> soil;

// Get the cost of flower seeds.
std::cout << "What do the flower seeds cost? " <<std::endl;
std::cin >> flower;

// Get the cost of the fence.
std::cout << "What does the fence cost? " <<std::endl;
std::cin >> fence;

// Calculate the total cost.
total = Soil + Flower + Fence;

// Display the total cost
std::cout << "The total cost is $" << total;
std::cout << "." << std::endl;

return 0;

std::string Soil;
[...]
std::string Flower;
[...]
std::string Fence;