#include <iostream>
using namespace std;


int Abv(int a,int b){
	if(a == b){
		return 1000000;
	}
	if(a > b){
		return a - b;
	}else{
		return b - a;
	}
}

int main(){
	int n;
	cin>>n;
	int x[n];
	int absv = 1000000;

	for (int i = 0; i < n ; ++i)
	{
		cin>>x[i];
	}

	for (int i = 0; i < n - 1; ++i)
	{
		for (int j = i + 1; j < n; ++j)
		{
			if( Abv(x[i],x[j]) <= absv ){
				absv = Abv(x[i],x[j]);
			}
		}
	}
	cout<<absv;
}