In this particular context, however, that should be just fine: low is clearly initialized to zero, and then only set to the value of this expression +1. As su

In this particular context, however, that should be just fine: low is clearly initialized to zero, and then only set to the value of this expression +1. As such, barring other bugs, low can never be negative. Your point is valid, though, and worth bearing in mind in other circumstances.