storing numbers in a matrix

but I think if you set your second for loop to go from 0 to i, then you'll get what you're looking for.err, No.

im confused on how to construct the for loop
Why do you have nested for loops. You are parsing one line of text at a time and that line of text contains from 0 to n distances which you need to add to your array. Each line you read in will have 1 more distance than the previous line so your 'i' index needs to increment every time you've read in a line and parsed it - it needs to be 0 for the first pass so it's probably best to increment it just before looping back to read in the next line. The 'j' index needs to be in a loop to add each of the distances to the array.

You need to think about what you are doing before you write code. Solve the problem using pen and paper before attempting code.

not entirely sure with the code what the IOException Catch is for...but oh well...

because in the .dat file (that i cant alter) i have to by pass all comments (*) and all cities (they have a , in their name)

this is my still unworking updated code

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.StringTokenizer;

public class City
{

private String[] cityList;
private String[] stateList;
private String[] longitudeList;
private String[] latitudeList;
private String[] populationList;
private String[][] distanceBetweenCities;
private boolean[] selectedCities;
private boolean[] selectedEdges;


public City()
{
cityList = new String[128];
stateList = new String[128];
longitudeList = new String[128];
latitudeList = new String[128];
populationList = new String[128];
distanceBetweenCities = new String[576][576];

try
{

//reads city and parses
BufferedReader in = new BufferedReader(new FileReader("miles.dat"));
String city; //reads in miles.dat

// read all the words from the file
System.out.println( "Reading miles.dat..." );
System.out.println();
int ctr = 0;
int milesIndex = 0;
int cityIndex = 1;

while( (city = in.readLine()) != null ) //continues till .dat files has no more lines
{
if(city.startsWith("*") != true) //skip comments
{
if(city.contains(",") == true) //finding words with ","
{

StringTokenizer st = new StringTokenizer(city, "," + "[" + "]");

cityList[ctr] = st.nextToken();
//System.out.println(cityList[ctr]);

stateList[ctr] = st.nextToken().replaceAll(" ", "");
//System.out.println(stateList[ctr]);

longitudeList[ctr] = st.nextToken();
//System.out.println(longitudeList[ctr]);

latitudeList[ctr] = st.nextToken();
//System.out.println(latitudeList[ctr]);

populationList[ctr] = st.nextToken();
//System.out.println(populationList[ctr]);
ctr++;

}

//city = in.readLine();
if(city.contains(",") != true)
{

while (milesIndex < cityIndex)
{

StringTokenizer st = new StringTokenizer(city);

while(st.hasMoreTokens())
{

distanceBetweenCities[cityIndex][milesIndex] = st.nextToken();
System.out.println(distanceBetweenCities[cityIndex][milesIndex]);
milesIndex++;
}

}
milesIndex = 0;
cityIndex++;
}

}

}

in.close(); //in closed
}







catch (IOException e)
{

}


}



public boolean[] selectAllCities()
{

selectedCities = new boolean[128];
for (int i = 0; i < 128; i++)
{
selectedCities[i] = true;

}
return selectedCities;

}

public boolean[] unselectAllCities()
{

selectedCities = new boolean[128];
for (int i = 0; i < 128; i++)
{
selectedCities[i] = false;

}
return selectedCities;

}

public boolean[] selectAllEdges()
{

selectedEdges = new boolean[128];
for (int i = 0; i < 128; i++)
{
selectedEdges[i] = true;

}
return selectedEdges;

}

public boolean[] unselectAllEdges()
{

selectedEdges = new boolean[128];
for (int i = 0; i < 128; i++)
{
selectedEdges[i] = false;

}
return selectedEdges;

}

public boolean[] printEdges()
{
for (int i = 0; i < 128; i++)
{
System.out.println(selectedEdges[i]);

}
return selectedEdges;
}

public static void main(String args[])
{

new City(); //calls a method

}

}

and im stuck here

if(city.contains(",") != true)
{

while (milesIndex < cityIndex)
{

StringTokenizer st = new StringTokenizer(city);

while(st.hasMoreTokens())
{

distanceBetweenCities[cityIndex][milesIndex] = st.nextToken();
System.out.println(distanceBetweenCities[cityIndex][milesIndex]);
milesIndex++;
}

}
milesIndex = 0;
cityIndex++;
}