#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=n-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define vtpl(x,y,z) vector<tuple<x,y,z>>
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=1e9+10;
const ll INF=4e18;
const ll dy[8]={1,0,-1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template<class T> inline bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}


const int mod = 1000000007;
const int max_n = 200005;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x=0):x((x%mod+mod)%mod){}
  mint operator-() const { return mint(-x);}
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod-a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;}
  mint operator+(const mint a) const { return mint(*this) += a;}
  mint operator-(const mint a) const { return mint(*this) -= a;}
  mint operator*(const mint a) const { return mint(*this) *= a;}
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t>>1);
    a *= a;
    if (t&1) a *= *this;
    return a;
  }
 
  // for prime mod
  mint inv() const { return pow(mod-2);}
  mint& operator/=(const mint a) { return *this *= a.inv();}
  mint operator/(const mint a) const { return mint(*this) /= a;}
};
istream& operator>>(istream& is, const mint& a) { return is >> a.x;}
ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}

struct combination {
  vector<mint> fact, ifact;
  combination(int n):fact(n+1),ifact(n+1) {
    assert(n < mod);
    fact[0] = 1;
    for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i;
    ifact[n] = fact[n].inv();
    for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i;
  }
  mint operator()(int n, int k) {
    if (k < 0 || k > n) return 0;
    return fact[n]*ifact[k]*ifact[n-k];
  }
}comb(max_n);


int main(){
    string s;cin >> s;
    ll n=s.size();
    vector<pl> lcnt(n,{0,0}),rcnt(n,{0,0});
    rep(i,n-1){
        lcnt[i+1].fi+=lcnt[i].fi;
        lcnt[i+1].se+=lcnt[i].se;
        if(s[i]=='A')lcnt[i+1].fi++;
        if(s[i]=='?')lcnt[i+1].se++;
    }
    per(i,n-1){
        rcnt[i].fi+=rcnt[i+1].fi;
        rcnt[i].se+=rcnt[i+1].se;
        if(s[i+1]=='C')rcnt[i].fi++;
        if(s[i+1]=='?')rcnt[i].se++;        
    }
    /*rep(i,n){
        cout << lcnt[i].fi <<" " << lcnt[i].se <<endl;
    }
    rep(i,n){
        cout << rcnt[i].fi <<" " << rcnt[i].se <<endl;
    }*/
    mint ans=0;
    rep(i,n){
        if(s[i]=='B'||s[i]=='?'){
            mint left=lcnt[i].fi;
            left*=mint(3).pow(lcnt[i].se);
            if(lcnt[i].se){
                mint l=lcnt[i].se;
                l*=mint(3).pow(lcnt[i].se-1);
                left+=l;
            }
            mint right=rcnt[i].fi;
            right*=mint(3).pow(rcnt[i].se);
            if(rcnt[i].se){
                mint r=rcnt[i].se;
                r*=mint(3).pow(rcnt[i].se-1);
                right+=r;
            }
            ans+=right*left;
        }
    }
    cout << ans <<endl;
}

Measured memory_bytes: 6784