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

int main() {
	long long n;
	cin>>n;
	map<long long, long long>Ox;
	long long dis=0,A=0,B=0;//distance
	bool zero_dis=0;
	for(long long i=1;i<=n && !zero_dis;i++){
		long long tmp;
		cin>>tmp;
		if(Ox[tmp]!=0){
			zero_dis=true;
			A=Ox[tmp];
			B=i;
			dis=0;
		}
		else Ox[tmp]=i;
	}
	
	if(!zero_dis){
		dis=-1;
		for(auto i= Ox.begin(),j=++Ox.begin(); j!=Ox.end(); i++, j++){//cout<<j->first<<" "<<i->first<<endl;
			long long tmp_dis=j->first-i->first;
			if(dis>tmp_dis||dis<0){
				dis=tmp_dis;
				A=j->second;
				B=i->second;
			}
		}
	}
	cout<<dis<<"\n"<<A<<" "<<B;
	return 0;
}