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Imagesnapdragon2003 wrote in Imagecpp

Hi, everyone. I'm just starting in C++, and one of my homework assignments is driving me INSANE. I'm sure it's a stupid error, but I can't seem to find it.

The webpage for the assignment is located at:
http://www.cwu.edu/~schwing/cs361/CPPprog2.html
You can get the plastic.dat file here.

I'm SURE the problem is in void performBucketSort(Supplier s[], int iSizeOfArray, int iMaxDigits). Argh!


#include <iostream>
#include <fstream>
#include <math.h>
using namespace std;

struct Supplier
{
   char companyID[5];
   int price;
};

void performBucketSort(Supplier s[], int iSizeOfArray, int iMaxDigits);
void printCheapestTenSuppliers(Supplier s[]);
int getSignificantDigit(int iNumber, int iPlacesFromRightmost);
const int MAX_DIGITS = 4;
const int SUPPLIERS_ARRAY_SIZE = 1000;

int main()
{
   // Create needed variables
   Supplier suppliers[SUPPLIERS_ARRAY_SIZE];
   ifstream fin("plastic.dat");

   for(int i = 0; i < SUPPLIERS_ARRAY_SIZE; i++)
   {
      cout << i << endl;
      fin >> suppliers[i].companyID >> suppliers[i].price;
   }

   cout << "read in file" << endl;

   for(int i = 0; i < 10; i++)
   {
      cout << suppliers[i].companyID << "          " << "$" << suppliers[i].price << endl;
   }

   // Now do the bucket sort...
   performBucketSort(suppliers, SUPPLIERS_ARRAY_SIZE, MAX_DIGITS);

   cout << "bucket sort performed" << endl;

   // Print out the top ten suppliers.
   printCheapestTenSuppliers(suppliers);

   // Read file into array of type Supplier
   
   // Do bucket sort

      // Get max number of digits
      // Loop over digits of the integers starting with least significant.
         // 
      
      // Distribution pass: Place each value of single-subscripted array into bucket in
      // double-subscripted array based on value in current digit position of loop.
      // For example, if the data is to be given by four digit integers and the current
      // digit being sorted in the loop is the 3rd, then 623 is placed in bucket 6, 9476
      // is placed in bucket 4 and 17 is placed in bucket 0.
      
      // Gathering pass: Values placed back into single-subscripted array by going in
      // order through each of the rows (buckets) and retrieving values in order from
      // each bucket. For the above numbers the retrieval order would be 17, 9476, 623.
      
      // Continue to loop until after consideration of the most significant digit. After
      // final gathering pass, the array is ordered.

   // Print cheapest ten suppliers

   // Use char as a placeholder
   char chExit;

   cout << "Press any key to exit... ";
   cin >> chExit;    // Once char has been read in, program will exit.
   // Use char as a placeholder

   cout << "Press any key to exit... ";
   cin >> chExit;    // Once char has been read in, program will exit.
}


// Bucket sort.  Pass in supplier array by reference.
void performBucketSort(Supplier s[], int iSizeOfArray, int iMaxDigits)
{
   // Create double-subscripted array.
   Supplier suppliersBucket[SUPPLIERS_ARRAY_SIZE][10];
   // int array
   int iSize[10];
   // We want enough slots that if for example, all numbers ended in 0,
   // they would all fit in the 0 bucket; therefore, we'll use
   // SUPPLIERS_ARRAY_SIZE for the number of slots.

   // Loop to control number of passes
   for(int iPass = 0; iPass < iMaxDigits; iPass++)
   {
      for(int i = 0; i < 10; i++)
      {
         iSize[i] = 0;
         cout << i << " " << s[i].companyID << " " << s[i].price;
      }

      // Loop to place numbers into buckets
      for(int i = 0; i < iSizeOfArray; i++)
      {
         // Store current number's significant digit
         int iSignificantDigit = getSignificantDigit(s[i].price, iPass);
         
         suppliersBucket[iSize[iSignificantDigit]][iSignificantDigit] = s[i];
         iSize[iSignificantDigit]++;
      }

      /////////////////////////////////////////
      // Now copy the numbers back in order. //
      /////////////////////////////////////////

      int iSlotToPlaceRecord = 0;
      for(int iCurrentBucket = 0; iCurrentBucket < 10; iCurrentBucket++)
      {
         for(int i = 0; i < iSize[i]; i++)
         {
            s[iSlotToPlaceRecord] = suppliersBucket[i][iCurrentBucket];
            iSlotToPlaceRecord++;

            if(i < 10)
            {
               cout << i << " " << s[iSlotToPlaceRecord].price << endl;
            }
         }
      }

      printCheapestTenSuppliers(s);
      char c;
      cin >> c;
   }
}

void printCheapestTenSuppliers(Supplier s[])
{
   cout << "Company ID          Price per Ton" << endl;

   for(int i = 0; i < 10; i++)
   {
      cout << i << " " << s[i].companyID << "          " << "$" << s[i].price << endl;
   }

   char chContinue;
   cout << "Press a key to continue... ";
   cin >> chContinue;
}


int getSignificantDigit(int iNumber, int iPlacesFromRightmost)   // 0 would be for the rightmost digit.
{
   // Following formula, if iPlacesFromRightmost is renamed to n, means:
   // Take the number you want to get a significant digit from, and get the remainder of 10^(n + 1)
      // Must add 1 to n if using it for mod because n is
      // one less than the power of 10 we want to use..
   // Divide result by 10^(n) and cast it to an int to get the single digit.
   // This will work on any number.
   return (int) (iNumber % (int) (pow(10, (iPlacesFromRightmost + 1))) / (int) (pow(10, iPlacesFromRightmost)));
}



I normally wouldn't be asking for help, but the program is already late, and I honestly cannot find the error. Please help???

Edit, 3:30 PM: Oh, and I'm using VS.Net 2003 Pro, if that helps. If possible, I would *really* like to try to solve this today... I need to go home for the weekend, and I have to catch the bus at 8:30pm. :-/ If that doesn't work out, I would still appreciate any help and suggestions!

LJ Video