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Comment by ronaldx | Hacker News Reader

I take your point here - but no developments in numeracy include counting objects from zero.

That's because making the switch from 1-indexing to 0-indexing is extremely counter-intuitive. However, take a hypothetical person who learned 0-indexing socially from birth, I'd imagine they'd be just as confused by 1-indexing.

When you use a count variable in programming, do you initialize it to 1?

Making this argument agrees with my general point: that high-level programming languages ought to count as humans do.

My point was that it's rather awkward to count from 1 when doing programming.

For instance, could you rewrite this function where int count = 1; and have it still be intuitive?

  int count_occurrences(std::vector<int> vec, int value) {
    int count = 0;
    for(int i = 0; i != vec.size(); ++i) { // using 0-based index
      if(vec[i] == value)
        ++count;
    }
    return count;
  }

My attempt is: (look how ugly!)

  int count_occurrences(std::vector<int> vec, int value) {
    if(vec.empty())
      return 0;
    count = 1;
    for(int i = 2; i <= vec.size(); ++i) { // using 1-based index
      if(vec[i] == value)
        ++count;
    }
    return count;
  }

As another commenter pointed out, it's only the indices that are one-based. I think it would look something like this:

  int count_occurrences(std::vector<int> vec, int value) {
    int count = 0;
    for(int i = 1; i <= vec.size(); ++i) { // using 1-based index
      if(vec[i] == value)
        ++count;
    }
    return count;
  }

Off the top of my head, this has a number of benefits in higher level languages. For instance in Javascript, here are some common inconveniences caused by zero-based indices:

  var lastEl = arr[arr.length - 1];

  if(arr.indexOf(someEl) !== -1) {
    // do something knowing that someEl is in the array
  }

and if we lived in a one-based world, here's what they would look like:

  var lastEl = arr[arr.length];

  if(arr.indexOf(someEl)) {
    // do something knowing that someEl is in the array
  }

It's only `i` (the index) that's meant to begin from 1.

`count` is a quantity, not an index, and there are such things as "zero apples". But you start counting them from the first one.

I agree that it's not at the same level, but there certainly are developments.

Computers aren't a development in numeracy?

Reply on news.ycombinator.com