issue with dynamic 2d char array

[truss86]

Hello!

I am working a programming assignment and the goal is to turn the static arrays into dynamic arrays. The program reads in a file of names, votes and outputs the winner and number of votes. I have the first dynamic array for votes complete, but I am having trouble getting the char array to work. Here is the code with all the functions.

main

#include "Ch9_Ex7.h"

int main()
{
    int numCandidates;
    char **allCandidates;
    int *votes, index, totalVotes;
    ifstream infile;

    infile.open("/Users/user/Documents/ch9ex7dynamic/ch9ex7dynamic/Ch9_Ex7Data.txt");
    if (!infile)
    {
        cerr << "Cannot open input file. Program terminates!" << endl;
        return 1;
    }

// read number of candidates
   
    readVotes (infile, votes, allCandidates, numCandidates);

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

    infile.close();

    totalVotes = sumVotes(votes, numCandidates);

    cout << left << setw(40) << "Candidate" <<  "Votes Received "
          << "   % of Total Votes" << endl;
    
    for (index = 0; index < numCandidates; index++)
        cout << left << setw(40) << allCandidates[index]
            << right << " " << setw(10) << votes[index] << "   " << setw(15)
            << (static_cast<double>(votes[index]) / static_cast<double>(totalVotes)) * 100 << endl;

    cout << "\nTotal:  " << totalVotes << endl;

    cout << "Winner: " << allCandidates[winnerIndex(votes,numCandidates)] << endl;
    system ("Pause");
    return 0;
}

function to read in the info

#include "Ch9_Ex7.h"

void readVotes (ifstream & infile, int * & votes,
                char ** & allCandidates, int & numCandidates)
{

// read number of candidates
    infile >> numCandidates;
    infile.ignore();  // carriage return

    votes = new int[numCandidates];
    allCandidates = new char*[numCandidates];
    
    for (int index = 0; index < numCandidates; index++)
    {
        infile >> votes[index];
        infile.ignore();  // space
        infile.get(allCandidates[index], MAX_NAME_LEN);
    }

}

get the total votes

int sumVotes(const int list[], int size)
{
    int sum = 0;

    for (int i = 0; i < size; i++)
        sum += list[i];

    return sum;
}

find winner

int winnerIndex(const int list[], int size)
{
    int maxIndex = 0;

    for (int i = 1; i < size; i++)
        if (list[i] > list[maxIndex])
            maxIndex = i;
    return maxIndex;
}

header

#ifndef Ch9_Ex7_h
#define Ch9_Ex7_h

#include <iostream>
#include <iomanip>
#include <fstream>

using namespace std;

int const MAX_CANDIDATES = 25;
int const MAX_NAME_LEN = 31; // includes NULL

int extern sumVotes(const int [], int);
int extern winnerIndex(const int [], int);
void extern readVotes (ifstream &, int * &, char **  , int &);

#endif

and here is the text file:

5
1150 Peter White
1205 Nancy Joneston
1500 Thomas Louis Johnson
1304 Abrigail Louise Fitzpatrick
1410 William Ryan O'Connor

any help would be much appreciated!

[mazzica1]

The problem in read votes is that you are using the 2nd dymetion without initializing it you need to do this

allCandidates[index]=new char[MAX_NAME_LEN];

just before

infile.get(allCandidates[index], MAX_NAME_LEN);