#include <iostream>
#include <vector>
#include <algorithm>

int main(void)
{
    int N; std::cin >> N;
    int K; std::cin >> K;
    std::vector<int> A(N);
    for (int i=0; i<N; i++){
        int a;
        std::cin >> a;
        A[i] = a;
        };

    int max = *std::max_element(A.begin(), A.end());
    int min = *std::min_element(A.begin(), A.end());

    std::cout << max - min << std::endl;
}