Unwanted blank line in output

When I run my program, it printed an unwanted blank line. Is there any way to fix this?

The output I wanted
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david 34 24 
ls 45 35
haha 56	23


What I got
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david 34 24 
//The unwanted blank line
ls 45 35
haha 56	23




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#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
int main()
{
	ifstream indata;
	indata.open("name.txt");
	
	int num[30];
	int num2[30];
	int n=0;
	string name[30];
	string nm;
	int n1,n2;
	
	while(getline(indata, nm, '\t'))
	{
		indata>>n1;
		indata.ignore();
		indata>>n2;
		indata.ignore();
		num[n]=n1;
		num2[n]=n2;
		name[n]=nm;
		n++;
	}

	int l;
	l=strlen(name[0].c_str());
	
//I converted the name(string) to nama(char) so that I can use the letters from the names separately
	
        char nama[3][l+1];
	
	for(int i=0; i<3; i++)
	{
		strcpy(nama[i], name[i].c_str());
		cout<<nama[i]<<" "<<num[i]<<" "<<num2[i]<<endl;
	}
	
	
	
	return 0;
}


My input file (name.txt) separated by tabs
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david	34	24 
ls	45	35
haha	56	23


Last edited on
//I converted the name(string) to nama(char) so that I can use the letters from the names separately


You can do that with strings.

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std::string testString("Beans on toast");

char x = testString[4]; // 's'
char y = testString[9]; // 't' 
You've got an extra space character at the end of the first line in names.txt. This means line 22 will discard the space instead of the newline character so that the newline ends up as part of the second name ("\nls").
Your input (underlined) is:
david	34	24 
ls	45	35
haha	56	23

Note the extra space at the end of the first line. This causes the second line name to be \nls.

To fix this, change lines 19-22 to:
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indata>>n1 >> n2;
indata.ignore(1000000, '\n');  // ignore a million characters or until newline is reached 

Technically, the first arg to ignore() should be numeric_limits<streamsize>::max(). This guarantees that it will read and discard every character until it finds a newline, no matter how obscenely huge the file is.

Other comments:
Why have variables nm, n1 and n2 at all? Why not read the values directly into their final locations?

Line 29: don't use l (lower case el) as a variable name. It's too easy to mistake it for 1 (digit one). For example, a casual reader might roll their eyes at line 34 and mistakenly change it char nama[3][2];

Speaking of line 34, it only works properly if the first name in the file is the longest one. Otherwise you'll overflow the strings.

Also speaking of line 34, you don't need it as repeater has pointed out.

I think it's clearer to put the "loopy" code in a for construct and have the body of a loop contain just the code that operates on each loop item, so I'd change line 17 to
for (n=0; getline(indata, nm, '\t'); ++n) and remove line 26.

Line 36 should be for(int i=0; i<n; i++)

Putting it all together:
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#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;
int
main()
{
    ifstream indata;
    indata.open("name.txt");

    int num[30];
    int num2[30];
    int n = 0;
    string name[30];

    for (n = 0; getline(indata, name[n], '\t'); ++n) {
	indata >> num[n] >> num2[n];
	indata.ignore(1000000, '\n');
    }

    for (int i = 0; i < n; i++) {
	cout << name[i] << " " << num[i] << " " << num2[i] << endl;
    }

    return 0;
}
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