Problems input

[DiegoTrivino]

If I have the following entry:
2

1
-1 0
-5 -3
2 5
0 0

1
-1 0
0 1
0 0

should read as java?? with a variable BufferedReader and readLine () method and read line by line? or just read a single line in the following format:

2 \ n \ n1 \ n-1 0 \ n-5 -3 \ n2 5 \ n0 0 \ n \ n1 \ n-1 0 \ n0 1 \ n0 0

[brianfry713]

Which problem number?

[DiegoTrivino]

I read only one line?
2 \ n \ n1 \ n-1 0 \ n-5 -3 \ n2 5 \ n0 0 \ n \ n1 \ n-1 0 \ n0 1 \ n0 0

or should I read several lines?

2

1
-1 0
-5 -3
2 5
0 0

1
-1 0
0 1
0 0

[brianfry713]

I'm not sure I understand what you're asking. On some problems it is best to parse the input line by line, on others you should read an int at a time.

[DiegoTrivino]

Thanks, I was able to fix the problem, but now I have a new problem with the entry:
if not tell me which is the termination condition, as I know I'll finish the entry?

[brianfry713]

I can't tell you how to parse the input without a problem description.

[Hikari9]

if you're asking about reading such input terminated by blank lines, that will work even if the last line has NO blank line, just check if the line read is a null string.

sample code:

Code: Select all

import java.util.*;
import java.io.*;

public class Main{
	public static void main( String args[] ) throws IOException{
	
		BufferedReader br = new BufferedReader( new InputStreamReader( System.in ) );
		
		String in;
		int n = Integer.parseInt( br.readLine() );
		
		br.readLine(); // ignore first blank line
		
		while( n-- != 0 ){
			while( ( in = br.readLine() ) != null ){ // will always work even if EOF
				// do stuff here
			}
		}
		
	}
}