code: func minIndex(indices ...int) int {
  	min := -1
  
  	for _, j := range indices {
  		if j < 0 {
  			continue
  		}
  		if min == -1 {
  			min = j
  		} else if j < min {
  			min = j
  		}
  	}
  	return min
  }
docs: // helper functions
  // returns the min index >= 0