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

long long a,minv=1000003;
int main(void){
    cin>>a;
	vector<long long> l;
long long c;
	for (int i = 0; i < a; ++i) {
		cin>>c;
		l.push_back(c);
	}
	l.erase(unique(l.begin(), l.end()), l.end());
    l.size();
	for (int i = 0; i < l.size()-1; ++i) {
		minv=min(abs(l[i+1]-l[i]),minv);
	}
	cout<<minv<<endl;


}