#include<bits/stdc++.h>
using namespace std;
#define int long long
#define REP(i,m,n) for(int i=(m);i<(n);i++)
#define rep(i,n) REP(i,0,n)
#define pb push_back
#define all(a) a.begin(),a.end()
#define rall(c) (c).rbegin(),(c).rend()
#define mp make_pair
#define endl '\n'
#define vec vector<ll>
#define mat vector<vector<ll> >
#define fi first
#define se second
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
typedef long double ld;
typedef complex<double> comp;
const ll inf=1e9+7;
const ll mod=2e5+3;
const int MAX=1000010;

signed main(){
    string s;cin>>s;
    ll n=s.size();
    vector<vector<ll> >dp(n+1,vector<ll>(26,-1));
    dp[0][26]=0;
    vector<vector<ll> >x(n+1,vector<ll>(26,-1));
    rep(i,n){
        ll c=s[i]-'a';
        rep(j,26){
            if(x[i][j]<0)continue;
            if(x[i+1][j]<0)x[i+1][j]=0;
            if(x[i+1][c]<0)x[i+1][c]=0;
            x[i+1][j]=(x[i+1][j]+x[i][j])%inf;
            if(j!=c)x[i+1][c]=(x[i+1][c]+x[i][j]%inf)%inf;
            else x[i+1][c]=(x[i+1][c]+x[i][c])%inf;
        }
        if(x[i+1][c]<0)x[i+1][c]=0;
        x[i+1][c]=(x[i+1][c]+1)%inf;
    }
    
    rep(i,n){
        ll c=s[i]-'a';
        rep(j,26){
            if(dp[i][j]<0)continue;
            if(dp[i+1][j]<0)dp[i+1][j]=0;
            if(dp[i+1][c]<0)dp[i+1][c]=0;
            dp[i+1][j]=(dp[i+1][j]+dp[i][j])%inf;
            if(j!=c)dp[i+1][c]=(dp[i+1][c]+dp[i][j]+x[i][j])%inf;
            else dp[i+1][c]=(dp[i+1][c]+dp[i][c])%inf;
        }
        if(dp[i+1][c]<0)dp[i+1][c]=0;
        dp[i+1][c]=(dp[i+1][c]+1)%inf;
    }
    ll ans=0;
    rep(i,26){
        if(dp[n][i]<0)continue;
        ans=(ans+dp[n][i])%inf;
        //cout<<dp[n][i]<<endl;
    }
    cout<<ans<<endl;
}