10 shapes, and one algorithm drawn with them
Built as a memo rather than a table: the thing worth hanging it up for reads across the room, with the full reference in smaller type below it.
Three sizes in one archive — from a sheet on the fridge to a poster on the wall.
Follow the arrows from START. The example is Euclid’s algorithm; shapes follow ISO 5807:1985.
Every other shape has exactly one exit: a step runs, a value is read, a line is printed — and the path carries on without asking anything. In the diagram above, 1 shape out of 7 is a diamond, and it is the only place where the path can split.
That is why a flowchart reads at a glance: the diamonds are its whole logic, and between them the path runs straight. The single arrow that goes back turns the three shapes under the diamond into a loop, which repeats until b reaches zero.
Hence the usual fault in other people’s diagrams: two lines leaving one rectangle. A question is hidden there that nobody wrote down, and the reader is left to guess it.
Why the numbers can be trusted. Every countable number here is computed from data rather than typed in, and the sheet must pass 7 independent checks before it is allowed to build — how many items there are, the order they come in, and the claim in the highlighted box itself. If one fails, there is no file.
