final_positions of the same length as nums.d seconds and store it in final_positions.final_positions in ascending order.prefix_sum to 0 and a variable total_distance to 0.final_positions using an index i:
a. Update total_distance by adding i * final_positions[i] - prefix_sum.
b. Add final_positions[i] to prefix_sum.total_distance modulo 10^9 + 7.