Thread: Please Help Me

Can someone please look at the following code and help me out ?
I am trying to calculate the total family income and size for a file of individuals. The assumption is that any person who has the same last neme as the previous person in the file is part of the same family ? I am not getting any errors but when I run the file I am getting some really strange numbers for total income and family size.

//familyTaxfile.cpp - reads in names of individuals, sorts alphabetically
//by the person's last name and calculates total income fpr a household and
//any applicable tax
//



#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using namespace std;
// Worker Type Definition

struct Worker {
string lname;
string fname;
double income;
float totalIncome;
int fSize;//size of family
};

const int WORKMAX = 10000;
void ReadWorkerFile(const string& fname, Worker w[], int& wCount);


int main()
{
Worker work[WORKMAX];
int workcount;
int i,j;
string fname;

cout<<"Enter the name of the file > ";
cin>>fname;


ReadWorkerFile(fname,work,workcount);

for (i = 0; i < workcount - 1; i++)
for (i = 0; i < workcount - 1; i++)
for(j = 0; j <workcount-1;j++)
if(work[j].lname>work[j+1].lname){
Worker tmp = work[j];
work[j] = work[j+1];
work[j+1]=tmp;
}
for (i = 0; i < workcount; i++)
cout<<work[i].lname<<" "<<
work[i].fname<<" $"<<work[i].income<<endl;

for (i = 0; i < workcount - 1; i++)
if(work[i].lname == work[i+1].lname){
work[i].totalIncome = work[i].totalIncome+work[i+1].income;
work[i].fSize++;
cout<<work[i].lname<<" "<<work[i].totalIncome<<" "<<work[i].fSize<<endl;
}

return 0;

You didn't include your function implementation

Implementation ? I am not quite sure what you are saying ?

What you included was the function prototype:

void ReadWorkerFile(const string& fname, Worker w[], int& wCount);

And a call to the function:

ReadWorkerFile(fname,work,workcount);

The implementation would be the function itself, ie:

Code:

//prototype
int AddInts(int FirstInt, int SecondInt);

//call to the AddInts function
int i=AddInts(2,2);

//function implementation
int AddInts(int FirstInt, int SecondInt)
{
    return(FirstInt+SeconInt);
}

//familyTaxfile.cpp - reads in names of individuals, sorts alphabetically
//by the person's last name and calculates total income fpr a household and
//any applicable tax
//



#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using namespace std;
// Worker Type Definition

struct Worker {
string lname;
string fname;
double income;
float totalIncome;
int fSize;//size of family
};

const int WORKMAX = 10000;
void ReadWorkerFile(const string& fname, Worker w[], int& wCount);


int main()
{
Worker work[WORKMAX];
int workcount;
int i,j;
string fname;

cout<<"Enter the name of the file > ";
cin>>fname;


ReadWorkerFile(fname,work,workcount);

for (i = 0; i < workcount - 1; i++)
for (i = 0; i < workcount - 1; i++)
for(j = 0; j <workcount-1;j++)
if(work[j].lname>work[j+1].lname){
Worker tmp = work[j];
work[j] = work[j+1];
work[j+1]=tmp;
}
for (i = 0; i < workcount; i++)
cout<<work[i].lname<<" "<<work[i].fname<<" $"<<work[i].income<<endl;

for (i = 0; i < workcount - 1; i++)
if(work[i].lname == work[i+1].lname){
work[i].totalIncome = work[i].totalIncome+work[i+1].income;
work[i].fSize++;
cout<<work[i].lname<<" "<<work[i].totalIncome<<" "<<work[i].fSize<<endl;
}

return 0;
}


void ReadWorkerFile(const string& fname, Worker w[], int& wCount)
{

ifstream f;
Worker tmp;
f.open(fname.c_str());
if (f.fail()) {
cerr<<"Cannot open input file "<<fname<<endl;
return;
}
wCount= 0;

while(f>>tmp.lname>>tmp.fname>>tmp.income){
w[wCount] = tmp;
wCount++;
}
f.close();

}

How will this affect my struct ?

like this:

lets say the file contains this:

Jones Mary 1555.66
Jones John 12000.56
Ghost Casper 444.55
Murphy Joe 1234.77
Murphy Jill 899999.88

On the first loop it would read in Jones but since x is 0 it will skip ahead and read in the rest of the info (trashing the fname, and reading in the amount of the money) it will also set the dependents to 1(so you need another int in your struct)

struct[0].fname="Jones"
x=1

Second loop it will read in the next line getting jones once again
struct[1].fname="Jones" since that is the same as struct[1-1].fname it will go to the then statement.
trashing the first name again, then adding the total income by the amount on this line, increase the dependants

x=1

Third loop it will read in the next line getting Ghost as a last name since this doesn't equal Jones it will read in the rest of the information at struct[x].

So at the very end of the read
struct[0].fname="Jones"
struct[1].fname="Ghost"
struct[2].fname="Murphy"
struct[3].fname="Murphy"

and you know how many families there is because x=3 (which is the correct number, just ignore the last struct) so pass x back so you know how many families there is.

If I can't find a run time error by reading the code I tend to throw a lot of cout statements in to monitor variable changes for several cycles of the code. Here, I would do it first in the ReadWorkerFile function to be sure everything is being read in as expected. Then I would try printing a few structs from work[] in main() to be sure they were retained in work[] appropriately, etc. At some point I can usually track down where the error is.

In this case, I am a bit suspicious about the validity of work[]. Given that you are declaring work[] to be an array of 10000 structs, I would be concerned that you are overloading the programs stack and getting erroneous values. If that is the case, as you work through the code with appropriately placed cout statements you'll find it. The way to fix it is to use dynamic memory to declare the memory for work[] rather than store it locally on the program stack. You can do that yourself with the new and delete operators for arrays, or you can use the vector class of STL (since you are already using the string class from STL) to do the dynamic memory business for you.