Question

My program works fine with if else conditions but when it is not working when I try to implement it using a for loop. Can you fix my for loop and please show me how to do this using loops?

I would appreciate if you could explain the loop that you are using.

/* Programming Challenge: Shipping Charges

The Fast Freight Shipping Company charges the following rates:

Weight of Package (in Kilograms) Rate per 500 Miles Shipped

2 kg or less $1.10

Over 2 kg but not more than 6 kg $2.20

Over 6 kg but not more than 10 kg $3.70

Over 10 kg but not more than 20 kg $4.80

Write a program that asks for the weight of the package and the distance it is to be

shipped, and then displays the charges.

Input Validation: Do not accept values of 0 or less for the weight of the package. Do

not accept weights of more than 20 kg (this is the maximum weight the company will

ship). Do not accept distances of less than 10 miles or more than 3,000 miles. These

are the company’s minimum and maximum shipping distances.

*/

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{

//CONSTANTS

const double RATE_0_2 = 1.10, RATE_2_6 = 2.20, RATE_6_10 = 3.70, RATE_10_20 = 4.80;

const double MIN_WEIGHT = 0, MAX_WEIGHT = 20, MIN_DIST = 10, MAX_DIST = 3000;

//Variables

double weight, distance, costPer500, totalCost;

// I/O

cout << "Enter the weight of the package in numbers only (Ex:12.75): ";

cin >> weight;

cout << "Enter the distance over which the package needs to be shipped: ";

cin >> distance;

//Formatting all numeric output to display numeric data to 2 decimal places

cout << setprecision(2) << fixed << endl;

//Running conditionals as per weight restrictions

if (weight < 0)

{

cout << "Invalid input. Weight cannot be negative (Ex: 25)" << endl;

cout << "The program will now halt. Press any key to terminate the program." << endl;

system("pause");

//If you call either of these 2 functions below, the program terminates instantly. The window flashes and disappears.

exit(EXIT_SUCCESS); //--> If argument to exit() is 0 or EXIT_SUCCESS, it indicates success. Terminates the process normally, performing the

//regular cleanup for terminating programs, and a successful termination status is returned to the host environment.

//exit(EXIT_FAILURE); --> If argument to exit() is EXIT_FAILURE, it indicates failure. Terminates the process normally, performing the

//regular cleanup for terminating programs, and an unsuccessful termination status is returned to the host environment.

}

else

if (weight >= 0 && weight <= 2)

costPer500 = weight * RATE_0_2;

else if (weight > 2 && weight <= 6)

costPer500 = weight * RATE_2_6;

else if (weight > 6 && weight <= 10)

costPer500 = weight * RATE_6_10;

else if (weight > 10 && weight <= 20)

costPer500 = weight * RATE_10_20;

else

{

cout << "Sorry, the maximum weight we accept is 20 kg. The program will now halt." << endl;

system("pause");

exit(EXIT_SUCCESS);

}

//This is just for testing the value stored in the variable costPer500 at this stage

//cout << "The cost of shipping per 500 miles is $" << costPer500 << endl;

/*

//Running conditionals as per distance restrictions

if (distance < 10 || distance > 3000)

{

cout << "Sorry, the minimum distance we accept is 10 miles and the maximum distance is 3000 miles." << endl <<

"The program will now halt. Press any key to terminate the program." << endl;

system("pause");

exit(EXIT_SUCCESS);

}

else if (distance >= 10 && distance <= 500)

{

totalCost = costPer500 * 1;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

else if (distance > 500 && distance <= 1000)

{

totalCost = costPer500 * 2;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

else if (distance > 1000 && distance <= 1500)

{

totalCost = costPer500 * 3;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

else if (distance > 1500 && distance <= 2000)

{

totalCost = costPer500 * 4;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

else if (distance > 2000 && distance <= 2500)

{

totalCost = costPer500 * 5;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

else if (distance > 2500 && distance <= 3000)

{

totalCost = costPer500 * 6;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

//Resetting cout to its default values

cout << defaultfloat;

cout << setprecision(0);

*/

//I could have also accomplished the distance restrictions using a for loop

if (distance < 10 || distance > 3000)

{

cout << "Sorry, the minimum distance we accept is 10 miles and the maximum distance is 3000 miles." << endl <<

"The program will now halt. Press any key to terminate the program." << endl;

system("pause");

exit(EXIT_SUCCESS);

}

else

{

int i, count = 1;

for (i = 0; i <= 3000; i = i + 500);

if (distance >= 10 && distance <= i)

{

totalCost = costPer500 * count;

cout << "The value of i is: " << i << endl;

cout << "The value of count is: " << count << endl;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

count = count + 1;

}

system("pause");

return 0;

}

Answer 1

The correct code for the FOR loop:

Explanation:

You need to run the for loop till (i <= distance) rather than( i<=3000) because you need to count how many 500 miles are there in the distance. Also for every iteration of the for loop, we will increase the count by 1 and the count variable will be initially initialized to zero.

Code (Text):

int i, count = 0;

for (i = 0; i <= distance; i = i + 500){

   count = count + 1;

}

if (distance >= 10 && distance <= i) {

totalCost = costPer500 * count;

cout << "The total cost for shipping the package is $" << totalCost << endl;

}

Sample Output:

Testing the for loop by printing cost using both if-else and for loop: