Stack with minimum using expanded data type

stackWithMinImp1.go

//the key to this implementation is using a different data structure in the stack.
//each val in the stack contains the current minimum at the time of insertion.
type stackVal struct { 
	val int
	min int
}

type stackWithMin struct {
	data []stackVal
}

func (s *stackWithMin) pop() int {
	popped := s.data[len(s.data)-1]
	s.data = s.data[:len(s.data)-1]
	return popped.val
}

func (s *stackWithMin) push(item int) {
	currentMin := s.min()
	if item < currentMin { //update the minimum in the stackVal struct
		currentMin = item
	}
	val := stackVal{
		val: item,
		min: currentMin,
	}
	s.data = append(s.data, val)
}

func (s *stackWithMin) min() int {
	if s.isEmpty() {
		return 100000000000000000 //Not the most elegant way to handle this, but if there is no min, just return a large number
	}
	data := s.data[len(s.data)-1]
	return data.min
}

func (s *stackWithMin) peek() int {
	data := s.data[len(s.data)-1]
	return data.val
}

func (s *stackWithMin) isEmpty() bool {
	return len(s.data) == 0
}