# This content is archived!

For the 2018-2019 school year, we have switched to using the WLMOJ judge for all MCPT related content. This is an archive of our old website and will not be updated.# Method 1

This is a classic difference array problem. Increase the total brightness by B at A and decrease it by B at A + L.

## Time complexity

\mathcal{O}(N)

## Space complexity

\mathcal{O}(N)

# Method 2

Since there are a maximum of 10^7 seconds in a show but 10^4 fireworks, we donâ€™t need such a big array that will mainly be empty. We can use coordinate compression to speed up the program and to reduce memory usage. However, both methods pass. Use a map as the difference array.

## Time complexity

\mathcal{O}(M\log M)

## Space complexity

\mathcal{O}(M)