#include<bits/stdc++.h>
#define CSP2026 using
#define RP namespace
#define PLUSPLUS std
CSP2026 RP PLUSPLUS;
#define debug(x) cout<<"clock="<<clock()<<' '<<#x<<'='<<(x)<<'\n'
//#define getchar getchar_unlocked
using ll=long long;
inline int rd(){int x=0,f=1;char ch=getchar();for(;!isdigit(ch);ch=getchar())if(ch=='-')f=-1;for(;isdigit(ch);ch=getchar())x=(x<<3)+(x<<1)+(ch^48);return x*f;}
inline ll rdll(){ll x=0;int f=1;char ch=getchar();for(;!isdigit(ch);ch=getchar())if(ch=='-')f=-1;for(;isdigit(ch);ch=getchar())x=(x<<3)+(x<<1)+(ch^48);return x*f;}
signed main(){
	int n=rd(),cnt=0;
	string s;cin>>s;
	if(s[n-5]!='H')++cnt;
	if(s[n-4]!='A')++cnt;
	if(s[n-3]!='P')++cnt;
	if(s[n-2]!='P')++cnt;
	if(s[n-1]!='Y')++cnt;
	for(int i=0;i<n-5;++i)if(s.substr(i,5)=="HAPPY")++cnt;
	cout<<cnt<<'\n';
}