Compare two vectors C++

Question

I was wondering is there any function to compare 2 string vectors to return the number of different(or the same) elements? Or i have to iterate over both of them and test it

Answer 1

I don't know of an existing function but writing one yourself shouldn't be too much trouble.

int compare(const vector& left, const vector& right) {
  auto leftIt = left.begin();
  auto rightIt = right.begin();
  auto diff = 0;
  while (leftIt != left.end() && rightIt != right.end()) {
    if (*leftIt != *rightIt) {
      diff++;
    }
    leftIt++;
    rightIt++;
  }

  // Account for different length vector instances
  if (0 == diff && (leftIt != left.end() || rightIt != right.end())) {
    diff = 1;
  }

  return diff;
}

Notes

• Omitted std:: prefix for brevity
• This function needs to be updated if it should handle vector instances of different lengths