Reading in only first couple lines of input file

[chara76]

I'm trying to create a program that reads in data for 3 separate days and analyzes it. The data file has 72 lines (24 for each day). I only want to read in data for the first day (first 24 lines), but I cannot figure out how to.
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#include <iostream> // Needed for normal cin & cout statements
#include <fstream> // Needed to read or write files on disk
#include <cstdlib> // Needed for exit
#include <cmath> // Needed for certain math functions
#include <string> // Needed to read strings
using namespace std;
int main()
{
// Initializes variables
double Data1, Data2, Data3, Total(0);
int k;

// Opens data file
ifstream infile;
infile.open("data.txt");

if(!infile)
{
cout<<"Unable to open file: Data.txt\n"; // Displays error message if data file cannot be opened
system("pause"); // Pauses command window
exit (0); // Exits program
}
else
{
for(k=1; k<=24; k++) //Counter to read first 24 lines
{
while(infile>>Data1>>Data2>>Data3) // Reads in 3 data items
{
if(Data1 > 1) // Ignores Data1 if it is 1 or 0
Total=Total+Data1; // Adds up Data1 for first 24 lines
}
}
cout<<Total<<endl;
}
system("pause"); //Pauses console window
return (0); // Ends program
}