import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UncheckedIOException;
import java.util.stream.Stream;

class Main {
    public static void main(String[] args) {
        no21();
    }

    // No.21 平均の差
    private static void no21(){
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));

               // 数字の個数
               int totalNumber;
               // グループ数
               String groups;
               // 数字
               String[] inputNumbers;
       
               try {
                   String tn = reader.readLine();
                   totalNumber = Integer.parseInt(tn);

                   groups = reader.readLine();

                   inputNumbers = new String[totalNumber];
                   
                   for(int i = 0; i < totalNumber; i++){
                        inputNumbers[i] = reader.readLine();
                   }
                   reader.close();
               } catch (IOException e) {
                   throw new UncheckedIOException(e);
               }

               int[] numbers = Stream.of(inputNumbers).mapToInt(Integer::parseInt).sorted().toArray();

               // 平均の差を求める
               System.out.println(numbers[totalNumber - 1] - numbers[0]);
    }
}