posSort method
Sort pos
Implementation
int posSort(ChessPos key1, ChessPos key2) {
if (key1.x > key2.x) {
return -1;
} else if (key1.x < key2.x) {
return 1;
}
if (key1.y > key2.y) {
return -1;
} else if (key1.y < key2.y) {
return 1;
}
return 0;
}