Collect the blocks

There exist a 2-Dimensional rectangular field of infinite length and breadth. N Iron Blocks are dropped onto this field from the sky at particular coordinates. However, it is made sure that only one block is dropped at a particular coordinate. You are standing at a particular location (X, Y) of the field. You have a magnet with a power M in your hand. A magnet of power M at coordinates (x1, y1)