Sort the mouse for left to right. Add mouse one at a time, keep a current time length that all included mouses can run to holes. And keep the current mapping. When adding new mouse, if min time hole for that mouse is not mapped, added, move on. If no empty hole on left for existing included mouses, pick the min hole from not mapped hole, added and move on. If min hole is occupied, and there are empty holes on the left, pick the closest empty hole, check if the max time if move all existing mouse to their left hole(only for mouses on right side of the empty hole), and the min time if the current mouse pick a non occupied hole. Pick the smaller time cost, add, rearrange accordingly.