#include<bits/stdc++.h>
using namespace std;
int n;
int ans1,ans2;
int sum=1e9;
int a[101];
inline int read(){
	int x=0,f=1;char s=getchar();
	while(s<'0'||s>'9'){if(s=='-')f=-1;s=getchar();}
	while(s>='0'&&s<='9'){x=x*10+s-'0';s=getchar();}
	return x*f;
}
int main(){
	n=read();
	for(int i=1;i<=n;i++){
		a[i]=read();
	}
	a[n+1]=a[1];
	for(int i=1;i<=n;i++){
		if(sum>abs(a[i]-a[i+1])){
			ans1=i,ans2=i+1;
			ans2%=n;
			sum=abs(a[i]-a[i+1]);
		}
	}
	cout<<ans1<<" "<<ans2;
	return 0;
}