#include <bits/stdc++.h>
using namespace std;

namespace
{
int X[ 100100 ];
}

int main()
{
int i;
int iD;
int N;
int iMin;

	cin >> N;
	for( i = 0; i < N; i++ ) cin >> X[ i ];

	sort( X, X + N );

	iMin = 2000000;
	for( i = 1; i < N; i++ )
	{
		iD = X[ i ] - X[ i - 1 ];
		if( iD > 0 && iMin > iD ) iMin = iD;
	}

	if( iMin == 2000000 )
		cout << 0 << endl;
	else
		cout << iMin << endl;

	return 0;
}