[RESOLVED] shipping calculator help

[Aelos]

Here is the assignment

Shipping Calculator: Global Courier Services will ship your package based on how much it weighs and how far you are sending the package. Packages above 50 pounds will not be shipped. You need to write a program in C that calculates the shipping charge.
The shipping rates are based on per 500 miles shipped. They are not pro-rated, i.e., 600 miles is the same rate as 900 miles or 1000 miles.

Here are the shipping charges -
Package Weight Rate per 500 miles shipped
• Less than or equal to 10 pounds $2.00
• More than 10 pounds but less than or equal to 50 pounds $4.50

Test Case 1:
Input Data:

Weight: 1.5 pounds
Miles: 200 miles (This is one 500 mile segment.)


So I googled and tried everything for the past 6 hours and nothing really helped. Every per 500 miles it is pro rated. I've tried subtracting 1 from 500 and dividing by 500 and I still don't get the test case results.

Here is my code:

#include <stdio.h>
#include <stdlib.h>

int main() {

	
	double weight, rate, shippingCharge, miles;

	// User enters the weight and mileage
	printf("Enter the weight of the package:");
	scanf("%lf", &weight);
	printf("Enter the amount of miles it would take:");
	scanf("%lf", &miles);
	
// When weight is greater than 50
if(weight > 50) {
	printf("Sorry, we only ship packages of 50 pounds or less. \n");
	}
	else
	// When weight is less than 10
	if(weight < 10) {
		rate = 2.00;
		shippingCharge = ((miles + 499) / 500 ) * rate;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is greater than 10
	else
	if(weight > 10) {
		rate = 4.50;
		shippingCharge = ((miles + 499) / 500) * rate;;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is less than or equal to 50
	else
	if(weight <= 50) {
		rate = 4.50;
		shippingCharge = ((miles + 499) / 500) * rate;
		printf("Shipping charge is $%.2lf \n", shippingCharge);	
	}
	
	system("pause");	
}

It just does not work....any suggestions?

PS: I tried the ceil function and it did not work. Perhaps I did it wrong?

[2kaud]

shippingCharge = ((miles + 499) / 500 ) * rate;

close. If we declare an int for the multiple value of the shipping miles to be used for the calculation (ie 1 for the first 500, 2 for 1000 etc) then consider

int multiple = int((miles + 499) / 500);

As miles is a double, you need to just use the integer part! Then multiply this by the rate to get the shipping charge.

Also, as the only change for the different weight is the rate to be used, within the if statements just set rate and then at the end of them have the calculation and the display.

Also note that your if conditions are not all needed. You already check for > 50, so you then need just to check for < 10. If not < 10 (the else part of the if), then it must be greater than 10 and <= 50. So you only need 1 if statement to set rate to either 2 or 4.5.

[Aelos]

shippingCharge = ((miles + 499) / 500 ) * rate;

close. If we declare an int for the multiple value of the shipping miles to be used for the calculation (ie 1 for the first 500, 2 for 1000 etc) then consider

int multiple = int((miles + 499) / 500);

As miles is a double, you need to just use the integer part! Then multiply this by the rate to get the shipping charge.

Also, as the only change for the different weight is the rate to be used, within the if statements just set rate and then at the end of them have the calculation and the display.

Also note that your if conditions are not all needed. You already check for > 50, so you then need just to check for < 10. If not < 10 (the else part of the if), then it must be greater than 10 and <= 50. So you only need 1 if statement to set rate to either 2 or 4.5.

I am sorry, I am not sure if I follow.

#include <stdio.h>
#include <stdlib.h>

int main() {

	
	double weight, rate, shippingCharge, miles, multiple;

	// User enters the weight and mileage
	printf("Enter the weight of the package:");
	scanf("%lf", &weight);
	printf("Enter the amount of miles it would take:");
	scanf("%lf", &miles);
	
// When weight is greater than 50
if(weight > 50) {
	printf("Sorry, we only ship packages of 50 pounds or less. \n");
	}
	else
	// When weight is less than 10
	if(weight < 10) {
		rate = 2.00;
		int multiple = int((miles + 499) / 500) * rate;
			result = shippingCharge;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is greater than 10
	else
	if(weight > 10) {
		rate = 4.50;
		int multiple = int((miles + 499) / 500) * rate;
			result = shippingCharge;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is less than or equal to 50
	else
	if(weight <= 50) {
		rate = 4.50;
		int multiple = int((miles + 499) / 500) * rate;
			result = shippingCharge;
		printf("Shipping charge is $%.2lf \n", shippingCharge);	
	}
	
	system("pause");	
}

I am confused to where you mean to insert that expression. I tried this, but got compile errors.

[2kaud]

int multiple = int((miles + 499) / 500) * rate;
result = shippingCharge;

becomes

int multiple = int((miles + 499) / 500);
shippingCharge = multiple * rate;

or shorter

shippingCharge = int((miles + 499) / 500) * rate;

The only issue with the original code calculation in post #1 is that the result of (miles + 499) / 500 needs to be truncated to an int as miles is a double. So if miles is say 200.0 then (200 + 499) / 500 = 1.398 - but you need this to be 1. So use int() to obtain the integer part - 1.

[Aelos]

int multiple = int((miles + 499) / 500) * rate;
result = shippingCharge;

becomes

int multiple = int((miles + 499) / 500);
shippingCharge = multiple * rate;

or shorter

shippingCharge = int((miles + 499) / 500) * rate;

The only issue with the original code calculation in post #1 is that the result of (miles + 499) / 500 needs to be truncated to an int as miles is a double. So if miles is say 200.0 then (200 + 499) / 500 = 1.398 - but you need this to be 1. So use int() to obtain the integer part - 1.

Ah I get it now! Thank you so much

[Aelos]

I'm sorry, another question. When I put this in, I still get a compile time error. It says: [Error] Expected expression before int...

#include <stdio.h>
#include <stdlib.h>

int main() {

	int multiple, miles;
	double weight, rate, shippingCharge;

	// User enters the weight and mileage
	printf("Enter the weight of the package:");
	scanf("%lf", &weight);
	printf("Enter the amount of miles it would take:");
	scanf("%lf", &miles);
	
// When weight is greater than 50
if(weight > 50) {
	printf("Sorry, we only ship packages of 50 pounds or less. \n");
	}
	else
	// When weight is less than 10
	if(weight < 10) {
		rate = 2.00;
		int multiple = int((miles + 499) / 500);
		shippingCharge = multiple * rate;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is greater than 10
	else
	if(weight > 10) {
		rate = 4.50;
		int multiple = int((miles + 499) / 500);
		shippingCharge = multiple * rate;
		printf("Shipping charge is $%.2lf \n", shippingCharge);
	}
	// When weight is less than or equal to 50
	else
	if(weight <= 50) {
		rate = 4.50;
		int multiple = int((miles + 499) / 500);
		shippingCharge = multiple * rate;
		printf("Shipping charge is $%.2lf \n", shippingCharge);	
	}
	
	system("pause");	
}

[2kaud]

if (weight <= 10) {
	rate = 2.00;
	shippingCharge = int((miles + 499) / 500) * rate;
	printf("Shipping charge is $%.2lf \n", shippingCharge);
}

This is for one calculation, the others are similar. This compiles OK for me with VS2017. If you are still getting compile errors, then post your revised code.

[2kaud]

Sorry. I forgot you are using c and not c++.

In c you need brackets around the int

if (weight <= 10) {
	rate = 2.00;
	shippingCharge = (int)((miles + 499) / 500) * rate;
	printf("Shipping charge is $%.2lf \n", shippingCharge);
}

[Aelos]

Thanks again, you are a lifesaver )

[2kaud]

Note that your code in post #6 can be shortened. You only need 1 if test and one printf statement. Consider

#include <stdio.h>
#include <stdlib.h>

int main()
{
	double weight, miles, rate;

	// User enters the weight
	printf("Enter the weight of the package:");
	scanf("%lf", &weight);

	// When weight is greater than 50
	if (weight > 50.0) {
		puts("Sorry, we only ship packages of 50 pounds or less.");
		return 0;
	}

	// User enters the mileage
	printf("Enter the amount of miles it would take:");
	scanf("%lf", &miles);

	// When weight is less than or equal 10
	if (weight <= 10.0)
		rate = 2.00;

	// When weight is greater than 10
	else
		rate = 4.50;

	// Calculate and display the result
	printf("Shipping charge is $%.2lf \n", (int)((miles + 499.0) / 500.0) * rate);

	system("pause");
}

[Aelos]

Looks 10x less complicated. Thanks for shortening it up

[CHerry :)]

Looks 10x less complicated. Thanks for shortening it up

If you try this formal for other test cases it gives out the wrong answers

Test Case 1:

Input Data:

Weight: 1.5 pounds

Miles: 200 miles (This is one 500 mile segment.)

Expected results:

Your shipping charge is $3.00

Test Case 2:

Input Data:

Weight: 5.6 pounds

Miles: 1200 miles (This is three 500 mile segments.)

Expected results:

Your shipping charge is $19.00

Test Case 3:

Input Data:

Weight: 11.0 pounds

Miles: 2000 miles (This is four 500 mile segments.)

Expected results:

Your shipping charge is $30.00

Test Case 4:

Input Data:

Weight: 38 pounds

Miles: 9600 miles (This is twenty 500 mile segments.)

Expected results:

Your shipping charge is $110.00

Test Case 5:

Weight: 55 pounds

Miles: 345 miles

Expected results:

Sorry, we only ship packages of 50 pounds or less.

[2kaud]

... and the issue in the code is ?

[noobcodezz]

... and the issue in the code is ?

Basically when compiled, the shipping charge comes out to $0 for any numbers inputted.

[noobcodezz]

Basically when compiled, the shipping charge comes out to $0 for any numbers inputted.

Nevermind, that was the original code. Not the corrected one. Sorry about that