If n != 0 and -1 cast to unsigned size_t divided by n is less than m. So that m times n would be bigger than size_t’s maximum value. Edit: inverted meaning sin

If n != 0 and -1 cast to unsigned size_t divided by n is less than m. So that m times n would be bigger than size_t’s maximum value. Edit: inverted meaning since check is for error, not for ok case.