How to read from a file line by line,token by token

[kilyx]

Hi everyone
i need to read from a file composed like this one

3
0 1 1
1 1 1
2 1 1
0 1
1 2
2 0

where the first line indicates the number of nodes in a graph
the lines with three numbers indicate the node,the number of outgoing edges,the number of incoming edges
the lines with two numbers indicate the edges

in my previous code i used to read the lines checking their lenght :if(str.length()==5),if(str.length()==3),if(str.le ngth()==1)
off course this checking method doesn't work if I have more than 9 nodes because i'll have some lines like
'10 x y' and their lenghts are not 1,3 or 5
so how can i read lines from a file distinguishing the lines with 3 numbers with the lines with 2 numbers?

thanks to everyone

[JosAH]

Read an entire line (it's a String) and split on one or more spaces "\\s+"; you get back an array of Strings, not containing spaces; when the array has three elements the original line represented a node/vertex; when the array contains two elements, the line represented an edge. The Integer.parseInt( ... ) method can transform the individual Strings to ints.

kind regards,

Jos

[kilyx]

thank you so much!