#include <bits/stdc++.h>
using namespace std;

#define rep(i,n) for(int i=0; i<(n); ++i)
#define rrep(i,n) for(int i=1; i<=(n); ++i)
#define drep(i,n) for(int i=(n)-1; i>=0; --i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define pb push_back
#define eb emplace_back
#define sz(x) (int)(x).size()
#define fi first
#define se second
#define v(T) vector<T>
#define imposs {cout<<"-1\n";return 0;}
#define LL_MAX LLONG_MAX
#define LL_MIN LLONG_MIN

typedef unsigned int uint;
typedef long long int ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int,int> pii;
typedef vector<pii> vpii;
typedef set<int> si;
typedef multiset<int> msi;
template<typename T>string join(const v(T)&v)
{stringstream s;rep(i,sz(v))s<<' '<<v[i];return s.str().substr(1);}
template<typename T>inline ostream& operator<<(ostream&o,const v(T)&v)
{if(sz(v))o<<join(v);return o;}

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

  string S;
  cin >> S;
  ll ans = 0;
  char n = '0';
  rep(i, sz(S)) {
    if (S[i] != n) {
      if (n != '0') ans++;
      if (i < sz(S)-1 && S[i] == S[i+1]) {
        if (n != '0') ans += (sz(S) - 1 - i);
        n = S[i];
      }
    }
  }
  cout << ans << '\n';
  return 0;
}

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
#define FOR(i, n) for(int (i)=0; (i)<(n); (i)++)
#define FOR1(i, n) for(int (i)=1; (i)<=(n); (i)++)
#define FORI(i, n) for(int (i)=n-1; (i)>=0; (i)--)
template<class T, class U> void umin(T& x, const U& y){ x = min(x, (T)y);}
template<class T, class U> void umax(T& x, const U& y){ x = max(x, (T)y);}
template<class T, class U> void init(vector<T> &v, U x, size_t n) { v=vector<T>(n, (T)x); }
template<class T, class U, typename... W> void init(vector<T> &v, U x, size_t n, W... m) { v=vector<T>(n);  for(auto& a : v) init(a, x, m...); }

int main(int argc, char** argv) {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cout << setprecision(15);
    if (argc == 2 && atoi(argv[1]) == 123456789) freopen("d:\\code\\cpp\\contests\\stdin", "r", stdin);

    const ll MOD = 1e9+7;
    int n;
    cin >> n;
    vector<int> v(n);
    FOR(i, n) cin >> v[i];
    v.push_back(0);
    sort(v.begin(), v.end());
    ll sol = 1;
    for(int i = 1; i<v.size(); i++)
        if (v[i] != v[i-1])
            sol = sol * (v[i] - v[i-1] + 1) % MOD;
    cout << sol << endl;
    if (argc == 2 && atoi(argv[1]) == 123456789) cout << clock()*1.0/CLOCKS_PER_SEC << " sec\n";
    return 0;
}

