Let we have a array of numbers with repetitions. How to create dictionary of frequencies in one line(without "for")? Any ideas?

EDIT: This has already been reported site-wide here. When I clicked the bar to show an answer which had been submitted after I had loaded the page, the new answer was loaded, but above the pagination controls. See the screenshot below (complete with freehand circle) for clarification.

Little Boxes code-golf ascii-art There's a song called Little Boxes about suburban sprawl that has lyrics as follows: Little boxes on the hillside, Little boxes made of ticky tacky, Little boxes on the hillside, Little boxes all the same. There's a green one and a pink one And a b...

You are given a wall of dimensions W x H, and a number of bullets, B (all integers > 0). You will fire all B bullets into the wall, which is a grid, uniformly at random. That is, each bullet fired must have an equal chance of landing in every cell on the grid. Cells on the grid look like this:...

Background In Boggle, a round is scored by adding up the points for each unique word a player has found (i.e. any word that more than one player has found is worth 0 points). The points are calculated based on the number of letters in each word, as follows: 3 letters: 1 point 4 letters: 1 poin...

Nichomachus's Theorem relates the square of a sum to the sum of cubes: and has a beautiful geometric visualization: Challenge: Create the 2d part of this visualization in ascii. You will need a minimum of four "colors." Two to distinguish between regions within a "strip" (ie, the differen...

Output # # # # # ##### ## # ## #### ####### # # ## #### ## ## # ### ####### # # # # ##### ### # # # # ### ###...

Ulam spiral 2 Like Ulam, I had a boring moment and began drawing a spiral like him's. But his version is utterly incorrect, as the \ diagonal distorts the equation n^2. The following picture illustrates an wrong Ulam spiral at left and a correct at right: I challenge you to output a numbered...