Code Doesn't Work Properly

[MasterKay]

My code doesn't show results after pressing 1 or 2. It just become blank. Why is this?

#include <iostream>
#include <string>
#include <fstream>

using namespace std;

size_t readNames(string filename, string surnames[], string firstnames[]);
void sortSurnameFirst (string [], string[], size_t);
void displayNames (string [], string[], size_t);
void sortFirstNames (string [], string [], size_t);

int main()
{
int const SIZE = 1000;
size_t count = 0;
int choice;

string names[SIZE];
string surnames[SIZE];

ifstream inputFile;
    string filename;
    int number;

    cout << "Enter the file name: ";
    cin >> filename;

    inputFile.open(filename.c_str());

if(inputFile)
{

while(count <SIZE && inputFile>>surnames[count] >> names[count])
{
count ++;
}

inputFile.close();

cout << " 1. Sort names by surnames then first names "<<endl;
cout << " 2. Sort names by first names then by surnames "<<endl;
cout<< "Enter your sorting choice: " ;
cin >> choice;

if (choice == 1)
{
cout<< "The names are sorted by surnames then first names"<<endl;
sortSurnameFirst (surnames, names,count);
displayNames(surnames, names,count);
}

if (choice == 2)
{
cout<< "The names are sorted by first names then surnames"<<endl;
sortSurnameFirst (surnames, names,count);
displayNames(surnames, names,count);
}

}

else
{
cout << "The following file doesnt exist" << endl;
}



return 0;
}






void sortSurnameFirst (string surnames[], string names[], size_t size)
{
bool swap;
string sort ;
string temp;
do
{
swap = false;
for (size_t i =0; i < size ; i++)
{
if (surnames[i] > surnames[i++])
{
sort = surnames[i];
surnames[i] = surnames[i++];
surnames[i++] = sort ;
swap = true;


}


if ( surnames[i] == surnames[i++] )
{
if (names[i] > names[i++] )
{
temp= names[i];
names[i] = names[i++];
names[i++] = temp ;
sort = surnames[i];
surnames[i] = surnames[i++];
surnames[i++] = sort ;

swap = true;
}
}



}

}
while (swap);
}


void displayNames( string surnames[], string names[], size_t size )
{

for ( size_t i =0; i < (size - 1) ; i++)
{
cout << surnames[i]<<" " << names[i] << endl;
}
}


void sortFirstNames (string surnames[], string names[], size_t size)
{
bool swap;
string sort1, temp1;
do
{
swap = false;

for ( size_t i =0; i < size ; i++)
{
if ( names[i] >names[i++] )
{
sort1 = names[i];
names[i] = names[i++];
names[i++] = sort1 ;
swap = true;

}
if ( names[i] == names[i++] )
{
if (surnames[i] > surnames[i++] )
{
temp1 = surnames[i];
surnames[i] = surnames[i++];
surnames[i++] = temp1 ;
sort1 = names[i];
names[i] = names[i++];
names[i++] = sort1 ;
swap = true;
}
}



}

}while (swap);
}

[Handy Andy]

Hello MasterKay,

With a quick look at your code the first thing I see is:

for (size_t i =0; i < size ; i++)
{
if (surnames[i] > surnames[i++])
{
sort = surnames[i];
surnames[i] = surnames[i++];
surnames[i++] = sort ;
swap = true;

By the time you finish with line 7 "i" will have the value of 4 because the "i++".

What you should have is:

for (size_t i =0; i < size ; i++)
{
if (surnames[i] > surnames[i + 1])
{
sort = surnames[i];
surnames[i] = surnames[i + 1];
surnames[i + 1] = sort ;
swap = true;

Second every sort routine I have seen is done with a nested for loop:

for (size_t i = 0; i < size; i++)
{
    for (size_t j = 1; j < size; j++)
    {
        // sort code here.
    }
}

There is a start until I can test the program.

Hope that helps,

Andy

[Handy Andy]

Hello MasterKay,

Some things I found while testing the program:

1. In the "sortSurnameFirst" function Keep in mind that any swap routine needs to swap two arrays not just one or not one at a time.

2. You can only sort by last name or first name. Not both at the same time. Otherwise this will jumble you names.

3. This code, starting at line 63, will never be seen because after it prints to the screen the program ends:

else
{
cout << "The following file does not exist" << endl;
}

after the "cout" you need way to pause before the program ends.

4. This prototype has no function definition. size_t readNames(string filename, string surnames[], string firstnames[]);. You have done the read in main.

Hope that helps,

Andy

[MasterKay]

The program still giving me problems... The names are not sorted properly.

Andy, please fix it like you tell me and try to run it. Create a random txt file titled "names" first and do it on your PC. If if works please show me the codes.

Thank you so far!

[MasterKay]

The program should be like this...

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

Name Sorting

Enter the file name: names.txt 1. Sort names by surnames then first names 2. Sort names by first names then surnames Enter your sorting choice: 1 ----------------------------------------------------- Surname First Name ----------------------------------------------------- Adams Grace Adams Hein Adams Samantha Babajide Pretty chadwick billy deWet Abel Olivier Vreda Venter Charlie Name Sorting ----------------------------------------------------- Enter the file name: names.txt 1. Sort names by surnames then first names 2. Sort names by first names then surnames Enter your sorting choice: 2 ----------------------------------------------------- Surname First Name ----------------------------------------------------- deWet Abel chadwick billy Venter Charlie Adams Grace Adams Hein 4 Babajide Pretty Adams Samantha Olivier Vreda