using namespace std;
#include <bits/stdc++.h>
#define BEGIN ios_base::sync_with_stdio(0);cin.tie(0);
#define END return EXIT_SUCCESS;
#define INF 1000007
#define FOR(I,A,B) for(int (I)=(A);(I)<(B);++(I))
#define ALL(C) (C).begin(),(C).end()
inline void solve()
{
	int N;cin>>N;
	vector<int>X(N);int A=INF;
	FOR(i,0,N)cin>>X[i];
	sort(ALL(X));
	FOR(i,0,N-1)
	  {
		if(X[i+1]==X[i])continue;
		A=min(A,X[i+1]-X[i]); 
	  }
	if(A==INF)cout<<0<<endl;
	else cout<<A<<endl;

}
int main(int argc,char**argv)
{
	BEGIN
	solve();
	END
}