//BAR-Salad Bar
#include<bits/stdc++.h>
using namespace std;
const int N=1e6+10;
int a[N],b[N],n;
stack<int>q;
char c[N];
int main(){
	cin>>n;
	int sum=0;
	a[0]=0;
	for(int i = 1;i <= n;i++){
		cin>>c[i];
		if(c[i]=='p') a[i]=a[i-1]+1;
		else a[i]=a[i-1]-1;
	}
	q.push(0);
	for(int i = n;i >= 0;i--){
		while(!q.empty() && a[q.top()]>a[i]) q.pop();
		if(!q.empty()) b[i]=q.top();
		if(q.empty() || q.top()==0) b[i]=n+1;
		q.push(i);
	}
	for(int i = 1;i <= n;i++){
		if(c[i]=='j')	continue;
		int ans=b[i-1]-i+1;
		while(c[b[i]]=='j' && b[i]>=i) ans--,b[i]--;
		sum=max(sum,ans);
	}
	cout<<sum;
}