// __builtin_popcount() ;
// multiset ;
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef string st ;
typedef long double ld ;
typedef pair<int, int> pi;
typedef pair<ll,ll> pl ;
typedef tuple<int,int,int>  ti ;
typedef tuple<ll,ll,ll> tl ;
typedef vector<vector<int>> vi ;
typedef vector<vector<ll>> vl ;
typedef vector<vector<bool>> vb ;
typedef vector<vector<st>> vs ;
typedef vector<vector<char>> vc;
const ll mod0 = 1000000007;
const ll mod1 = 998244353 ;
const ll LINF =  1000000000000000000 ;  //(10^18)
const int INF = 1000000000 ;            // (10^9)
 
 
#define pb                push_back
#define ppb               pop_back
#define pf                push_front
#define ppf               pop_front
#define all(x)            x.begin(), x.end()
#define rep(i,a,n)        for (ll i = a; i <= (n); ++i)
#define re                return 0;
#define fore(i,a)         for(auto &i:a)
#define V                 vector
 
 
ll gcd(ll a, ll b){
 
   if(b == 0){
    return a;
}
return gcd(b,a%b) ;
}
 
 
ll lcm(ll a, ll b){
    
    ll ans = a*b /gcd(a,b) ;
    return ans ;
}
 
// true --→ 素数　、false --→　素数じゃない
bool nis(ll a){
    bool flag = true ;
    rep(i,2,sqrt(a)+1){
        if(a%i == 0){
          flag = false ;
          break ;
}
}
 return flag ;   
}

 ll jun(ll a,ll b, ll c,ll rank ){
     
    vector<ll> ANS ;
    ANS.pb(-LINF) ;
    ANS.pb(a) ;
    ANS.pb(b) ;
    ANS.pb(c) ;
    
    sort(all(ANS)) ;
    return ANS[rank] ;
}

#define  C            cout   
#define  E            "\n";


//  UF.initはいっかいだけならいいけど、二回目以降はrepで初期化
vector<ll> par;
class UnionFind {
public:
 
  
   
  // サイズをＧＥＴ！
  void init(ll sz) {
       par.resize(sz,-1);
}
   // 各連結成分の一番上を返す
  ll root(ll x) {
    if (par[x] < 0) return x;
    return par[x] = root(par[x]);
  }
   
  // 結合作業
  bool unite(ll x, ll y) {
    x = root(x); y = root(y);
    if (x == y) return false;
    if (par[x] > par[y]) swap(x,y);
    par[x] += par[y];
    par[y] = x;
    return true;
  }
  // 同じグループか判定
  bool same(ll x, ll y) { return root(x) == root(y);}
  // グループのサイズをＧＥＴ！
  ll size(ll x) { return -par[root(x)];}
};
 
UnionFind UF ;
 
 
 
 st Y = "Yes" ; 
 st YY = "No" ;
 
 

void chmin(ll& x ,ll y){x = min(x,y) ;}
void chmax(ll& x ,ll y){x = max(x,y) ;}


vector<ll> Y4 = {0,1,0,-1} ;
vector<ll> X4 = {1,0,-1,0} ;

vector<ll> Y8 = {0,1,1,1,0,-1,-1,-1} ;
vector<ll> X8 = {1,1,0,-1,-1,-1,0,1} ;


vector<ll> enumdiv(ll n) { 
    vector<ll> S;
    for (ll i = 1; i*i <= n; i++) if (n%i == 0) { S.pb(i); if (i*i != n) S.pb(n / i); }
    sort(S.begin(), S.end());
    return S;
}
 
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
template<typename T> using max_priority_queue = priority_queue<T, vector<T>, less<T>> ;
//　使用例　min_priority_queue<ll (ここは型)> Q ;

st KU = " " ;


V<ll> prime_broken(ll a){
    
    V<ll> ans ;
    for(ll i = 2 ;i*i<=a;i++){
        if(a %i == 0){
          while(a %i == 0){
                a /= i ;
                ans.pb(i) ;
          }
            
        }
        
    }
    
    if(a != 1)ans.pb(a) ;
    return ans ;
}


const ld pai = acos(-1) ;
using P = pair<ll,ll> ;
using Edge = tuple<ll,ll,ll> ;


 st zz = "abcdefghijklmnopqrstuvwxyz" ;
 st ZZ = "ABCDEFGHIJKLMNOPQRSTUVWXYZ" ;

ll dist[1 << 18] ;
vector<ll> GG[1 << 18] ;

void bfs(ll N ,ll a){
     queue<ll> Q ;
     Q.push(a) ;
     
     rep(i,0,N){
        dist[i] = -1 ;         
     }
     dist[a] = 0 ;
     while(!Q.empty()){
         ll pos = Q.front() ;
         Q.pop() ;
         
         fore(u,GG[pos]){
             if(dist[u] == -1){
                 dist[u] = dist[pos] + 1 ;
                 Q.push(u) ;
             }
         }
     }
}

int main(void){ 
ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);

  
// nis(ll a) 素数判定
// jun(ll a,ll b,ll c, ll d) 三つのなかのd番目
// gcd(ll a , ll b) gcd 
// lcm(ll a ,ll b ) lcd 
// UF  UF.init(ll N) ; UF.root(i) ; UF.unite(a,b) ; UF.same(a,b) ; UF.size(i) ;
// enumdiv(ll a )約数列挙
// prime_broken(ll p) aのb乗のかたちででてくる 配列で受け取る
// bfs(ll N , ll a ) N = 頂点数 , a = 始点　

ll N ;
cin>>N ;

st S ;
cin>>S ;


V<ll> A(N) ;
V<ll> B(N) ;
for(ll i = N-1 ; i>= 0; i--){
    B[i] = 25 ;
    for(ll j = 0 ;j <= 25 ;j++){
        if(zz[j] == S[i]){
            A[i] = j ;
            break ;
        }
        
    }
    
 
}


for(ll i = N-1 ; i >= 0 ;i--){
    B[i] -= A[i] ;
}

rep(i,0,N-1){
    C << zz[B[i]] ;
}
C << E
 // if(dx < 0 || dy < 0 || dx >= W || dy >= H) continue ;
 // ld p  = sqrt(abs((A[i] - A[j])*(A[i] - A[j])) + abs((B[i] - B[j])*(B[i] - B[j]))) ;
 // C << fixed << setprecision(10) << 
re
}