#include <bits/stdc++.h>
#pragma GCC optimize ("O2,unroll-loops")
//#pragma GCC optimize("no-stack-protector,fast-math")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, int> piii;
typedef pair<ll, ll> pll;
#define debug(x) cerr<<#x<<'='<<(x)<<endl;
#define debugp(x) cerr<<#x<<"= {"<<(x.first)<<", "<<(x.second)<<"}"<<endl;
#define debug2(x, y) cerr<<"{"<<#x<<", "<<#y<<"} = {"<<(x)<<", "<<(y)<<"}"<<endl;
#define debugv(v) {cerr<<#v<<" : ";for (auto x:v) cerr<<x<<' ';cerr<<endl;}
#define all(x) x.begin(), x.end()
#define pb push_back
#define kill(x) return cout<<x<<'\n', 0;

const int inf=1000000010;
const ll INF=10000000000000010LL;
const int mod=1000000007;
const int MAXN=100010, LOG=20;

ll n, m, k, u, v, x, y, t, a, b, ans;
int A[MAXN], ps[MAXN], nxt[MAXN][3], nxt2[MAXN];
ll dp[MAXN];
string S;

int main(){
	ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
	cin>>S;
	n=S.size();
	for (int i=1; i<=n; i++){
		A[i]=(S[i-1]=='b')+1;
		ps[i]=(A[i]+ps[i-1])%3;
	}
	nxt[n+1][0]=nxt[n+1][1]=nxt[n+1][2]=nxt2[n+1]=n+1;
	for (int i=n; i; i--){
		nxt[i][0]=nxt[i+1][0];
		nxt[i][1]=nxt[i+1][1];
		nxt[i][2]=nxt[i+1][2];
		nxt2[i]=nxt2[i+1];
		nxt[i][ps[i]]=i;
		if (1<i && A[i-1]==A[i]) nxt2[i]=i;
	}
	if (nxt2[1]==n+1) kill(1)
	dp[0]=1;
	for (int i=0; i<n; i++){
		dp[i]%=mod;
		if (ps[n]==ps[i] && i) ans=(ans + dp[i])%mod;
		dp[i+1]+=dp[i];
		
		int pos=nxt2[i+1];
		int c=3^A[i+1];
		int j=nxt[pos][(c+ps[i])%3];
//		debug2(i, j)
		dp[j]+=dp[i];
	}
	ans=(ans + dp[n])%mod;
	cout<<ans<<"\n";
	
	return 0;
}
