randRangeWeighted(1, 9, 0, 0.5)
randRange(1, 9)
randRange(2, 9)
100 * A_100 + 10 * A_10 + A_1
randRange(0, A_100 - 1)
randRange(0, A_10 - 1)
randRange(0, A_1 - 1)
100 * B_100 + 10 * B_10 + B_1
0
graph.subtractor = new Subtractor( A, B );
graph.subtractor.show();
NUM_HINTS = graph.subtractor.getNumHints();
A - B
graph.subtractor.showHint();