[nickloewen]

OK I had to write things down to try and make sense of this. If anyone is like me, consider this loop that loops 5 times... maybe it will help?

  defines = 0
  tests = 0
  increments = 0

  defines++
  for (let i = 0; i < 5; i++) {
    tests++
    increments++
  }

  console.log(`defines: ${defines}, tests: ${tests}, increments: ${increments}`)

For the sake of space I'm not going too copy nested versions of that, but imagine nesting it two and then three levels deep.

  1 level will increment 5 (5^1) times    
  2 levels will increment 25 (5^2) times    
  3 levels will increment 125 (5^3) times

More interesting are the number of definitions and tests:

  levels    tests    defines
  1         15       1 
  2         30       6
  3         155      31

But I don't know is how the interpreter works and whether it has tricks to shrink those numbers; those just reflect my naive mental model of how things work.

[whatyoucantsay]

The confusion here is about math, not syntax.

N^2 is polynomial.

2^N is exponential.

https://stackoverflow.com/questions/4317414/polynomial-time-...