package server func (server *Server) validateRow(row string) (valid bool) { // Declarations baby! valid = true var found bool var double bool count := make(map[rune]int) // 1. Make sure row is 9 in length if len(row) != 9 { valid = false } // 2. Ensure all digits are numbers for _, value := range row { found = server.validChar(value) } if !found { valid = false } // 3. Ensure all digits (except zero) are only present once for _, digits := range row { count[digits] = count[digits] + 1 } for key, value := range count { if value > 1 && key != 48 { double = true } } if double { valid = false } return }