#include <iostream>
#include <algorithm>
using namespace std;

int main(){
	int N;
	int X[100000];
	fill(X, X + 100000, 1000000);
	cin >> N;
	for(int i = 0; i < N; i++){
		cin >> X[i];
	}
	
	sort(X, X+N);
	for(int i = 0; i < N; i++){
		for(int j = i+1; j < 100000; j++){
			if(X[i] == X[j]){
				X[j] = 100000;
				N--;
			}else {
				break;
			}
		}
		sort(X, X+N);
	}
	int a = X[2] - X[1], b = X[1] - X[0];
	if(a < b){
		cout << a << endl;
	}else {
		cout << b << endl;
	}
	
	return 0;
}