/*
ID: antwand1
TASK: barn1
LANG: C++
*/
#include <bits/stdc++.h>
#define ll long long
#define du long double
#define F first
#define S second
using namespace std;
vector<int> vec;
const int N=67108880;
string s;
int n,idx,lef,righ;
int mask;
du mn=1;
du dp[N];
int pre[112345][26];
bool ok(int&l,int&r,int&mask)
{
for(int i=0;i<26;i++){
int q=pre[r][i]-pre[l-1][i];
if(q){
q=(1<<i)&mask;
if(q==0)return 0;
}
}
return 1;
}
int bs(int mask,int le)
{
int l=le,r=n,ret=le-1;
while(l<=r){
int mid=(l+r)/2;
if(ok(le,mid,mask)){
ret=mid;
l=mid+1;
}
else r=mid-1;
}
return ret;
}
int bs2(int mask,int le)
{
int r=le,l=1,ret=le+1;
while(l<=r){
int mid=(l+r)/2;
if(ok(mid,le,mask)){
ret=mid;
r=mid-1;
}
else l=mid+1;
}
return ret;
}
du solve(int mask,int l,int r)
{
vec.push_back(mask);
du&ret=dp[mask];
if(ret)return ret;
r=bs(mask,r)+1;
l=bs2(mask,l)-1;
du f=0;
for(int i=0;i<26;i++){
int q=pre[r-1][i]-pre[l][i];
if(q)f++;
ret+=q;
}
ret=f/ret;
if(l!=0){
int ad=s[l]-'a';
ad=(1<<ad);
ret=min(ret,solve(mask|ad,l,r));
}
if(r!=n+1){
int ad=s[r]-'a';
ad=(1<<ad);
ret=min(ret,solve(mask|ad,l,r));
}
return ret;
}
void get(int mask,int l,int r)
{
du&ret=dp[mask];
if(ret)return;
r=bs(mask,r)+1;
l=bs2(mask,l)-1;
du f=0;
for(int i=0;i<26;i++){
int q=pre[r-1][i]-pre[l][i];
if(q)f++;
ret+=q;
}
ret=f/ret;
if(ret<mn){
mn=ret;
lef=l+1;
righ=r-1;
}
if(l!=0){
int ad=s[l]-'a';
ad=(1<<ad);
get(mask|ad,l,r);
}
if(r!=n+1){
int ad=s[r]-'a';
ad=(1<<ad);
get(mask|ad,l,r);
}
return;
}
main()
{
//freopen("barn1.in","r",stdin);freopen("barn1.out","w",stdout);
cin>>n;
cin>>s;
s="#"+s;
for(int i=1;i<=n;i++){
for(int j=0;j<26;j++){
pre[i][j]=pre[i-1][j]+(s[i]-'a'==j);
}
}
for(int i=1;i<=n;i++){
mask=1<<(s[i]-'a');
du u=solve(mask,i,i);
if(u<mn){
mn=u;
idx=i;
}
for(int i=0;i<vec.size();i++)dp[vec[i]]=0;
vec.clear();
}
mask=1<<(s[idx]-'a');
mn=2;
get(mask,idx,idx);
cout<<lef<<" "<<righ<<endl;
}
