Loop and a half before runtime exception

[erandall]

I changed my 2D array call in the proto and def--no linker error this time. This time I tossed in a couple of cout's and found out my loop: read name-5 ints (2 digit)-name-3 ints and the first digit of the fourth int.

Then it threw a:
Unhandled exception at 0x01053ef6 in AssignmentNine.exe: 0xC0000005: Access violation writing location 0xcccccccc.

//Declaration in Funcs9Ex13.h
//	Header guard
#ifndef FUNCS9EX13_H
#define FUNCS9EX13_H
//[No namespace declared]
//	Include files

#include <iostream>
#include <fstream>
#include <cstring>
#include <string>
#include <iomanip>

void fnReadNamesAndScores(std::ifstream&, std::string*, int*);

//Definition in Funcs9Ex13.cpp
#include "Funcs9Ex13.h"

using namespace std;

void fnReadNamesAndScores(ifstream &inFile, string OneDimArrOfStr[], int TwoDimArrOfInt[][NUMB_TESTS])
{
	int i = 0;
	while(inFile) {
		inFile >> OneDimArrOfStr[i];
		int score = 0, j = 0;
		while(score) {
			inFile >> TwoDimArrOfInt[i][j];
			j++;
		}
		i++;
	}
}

//Implementation in Grades9-13.cpp
#include "Funcs9Ex13.h"

using namespace std;

const int NUMB_STUDENTS = 10;
const int NUMB_TESTS = 5;
int main()
{
	ifstream ReadFile;
	fnOpenFiles(ReadFile, "ch9_Ex13Data.txt");

	string arrNames[NUMB_STUDENTS];
	int arrScores[NUMB_STUDENTS][NUMB_TESTS];

	fnReadNamesAndScores(ReadFile, arrNames, *arrScores);
	
		system("pause");
	return 0;

Now what am I doing wrong? (arrays, structs and classes have given me problems since I first tried learning C++ in 2002 before I became a mountain hermit for a few years. I'm still denting my brain pan against brick.)

Whether I get this fixed in time to turn it in tomorrow night, I WILL get it to work. Eventually.

ERandall

[Athar]

Run the debugger to see where the problem occurs.
The address 0xcccccccc smells like an uninitialized (pointer) variable.

[cire]

I'm rather surprised that links.

int* is not the same type as int TwoDimArrOfInt[][NUMB_TESTS] so the code should fail to link.

I would suggest changing line 14 to

void fnReadNamesAndScores(std::ifstream&, std::string[], int[][NUMB_TESTS]);

and then changing line 50 to:

fnReadNamesAndScores(ReadFile, arrNames, arrScores);

Notice the lack of asterisk.

When you do:

fnReadNamesAndScores(ReadFile, arrNames, *arrScores);

the array name is demoted to type int* and then you dereference it, meaning you're passing the value of the first uninitialized int value and it's being interpreted as an address. In debug configurations (using VC++,) uninitialized variables contain the bit pattern for 0xcccccccc which explains your error message.


By the way, the while control condition on line 27 can never true.