// http://processing.org/reference/sort_.html

// http://processing.org/reference/reverse_.html

The idea is sort() then reverse() your hiScore table Array:

// http://processing.org/reference/sort_.html
// http://processing.org/reference/reverse_.html

final int ENTRIES = 10, MAX = 10000;
int[] hiScore = new int[ENTRIES];

for ( int i = 0; i != ENTRIES; hiScore[i++] = (int) random(MAX) );

println(hiScore);
println();

hiScore = reverse( sort(hiScore) );
println(hiScore);

exit();

^ you've used GoToLoop's example too literally here, it was only an example. you load the scores into lines[] (line 2) and then do nothing else with them, instead setting hiScore[] to random values (line 3).

also, be careful that when you sort the loaded values that you aren't sorting them alphabetically rather than numerically given that they are strings.