# Latest posts

## Deep Reinforcement Learning

Stable Baselines rely on TF 1.x but Stable Baselines v3 rely on PyTorch.

## AlphaGo and Alpha Zero

In December 2016 we presented it at ENS Paris-Saclay with Étienne Simon but apparently I never wrote a blog post in the end.

## Six dates importantes en algorithmique

-300
Algorithme d’Euclide (qui date peut-être de l’école de Pythagore 530 av. J.C.)

## Quadrangle Inequality trick for dynamic programs

Application: Given an ordered list of keys with frequencies, build a binary search tree on those keys which minimizes the average query cost.

## Pareto optimality

Compute the pareto set of a given set of points in 2 or 3 dimensions.

## Multiplying polynomials

You are given two polynomials $P$ and $Q$ and want to compute their product. The polynomials are given in form of an array with their coefficients.

## Making pairs adjacent at minimal cost

You are given an array $X$ with the promise that each of its values appears exactly twice. You want to transform $X$ such that at the end all pairs are adjacent in the array. An allowed operation consists in removing a value from $X$ and appending it at the end. The cost of a solution is the maximal value which was moved.

## Identifying the maximum in a sliding window

Given an array $x$ and an integer $k$, determine for every index $1 \leq j\leq n$ the maximum $x[i]$ among all indices $\max\{1,j-k+1 \} \leq i \leq j$.

## Maintaining sum of k largest items in a dynamic set

Maintain a set, allowing to add or remove elements and to query the sum of the up to k largest items.