#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define FOR(i,n,m) for(int i=(n);i<(m);i++)
#define REP(i,n) FOR(i,0,n)
#define REPR(i,n) for(int i=(n);i>=0;i--)
#define all(vec) vec.begin(),vec.end()
using vi=vector<int>;
using vvi=vector<vi>;
using vl=vector<ll>;
using vvl=vector<vl>;
using P=pair<ll,ll>;
using PP=pair<ll,P>;
using vp=vector<P>;
using vpp=vector<PP>;
using vs=vector<string>;
#define fi first
#define se second
#define pb push_back
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(a>b){a=b;return true;}return false;}
const ll MOD=1000000007LL;
const int INF=1<<30;
const ll LINF=1LL<<60;
template<int mod>
struct ModInt{
    int x;
    ModInt():x(0){}
    ModInt(long long y):x(y>=0?y%mod:(mod-(-y)%mod)%mod){}
    ModInt &operator+=(const ModInt &p){
        if((x+=p.x)>=mod)x-=mod;
        return *this;
    }
    ModInt &operator-=(const ModInt &p){
        if((x+=mod-p.x)>=mod)x-=mod;
        return *this;
    }
    ModInt &operator*=(const ModInt &p){
        x=(int)(1LL*x*p.x%mod);
        return *this;
    }
    ModInt &operator/=(const ModInt &p){
        *this*=p.inverse();
        return *this;
    }
    ModInt operator-()const{return ModInt(-x);}
    ModInt operator+(const ModInt &p)const{return ModInt(*this)+=p;}
    ModInt operator-(const ModInt &p)const{return ModInt(*this)-=p;}
    ModInt operator*(const ModInt &p)const{return ModInt(*this)*=p;}
    ModInt operator/(const ModInt &p)const{return ModInt(*this)/=p;}
    bool operator==(const ModInt &p)const{return x==p.x;}
    bool operator!=(const ModInt &p)const{return x!=p.x;}
    ModInt inverse()const{
        int a=x,b=mod,u=1,v=0,t;
        while(b>0){
            t=a/b;
            a-=t*b;
            swap(a,b);
            u-=t*v;
            swap(u,v);
        }
        return ModInt(u);
    }
    friend ostream &operator<<(ostream &os,const ModInt<mod> &p){
        return os<<p.x;
    }
    friend istream &operator>>(istream &is,ModInt<mod> &a){
        long long x;
        is>>x;
        a=ModInt<mod>(x);
        return (is);
    }
};
const int mod=1e9+7;
using mint=ModInt<mod>;
mint mpow(mint x,ll n){
    if(!n){
        return mint(1);
    }
    if(n%2){
        return mpow(x,n-1)*x;
    }
    mint t=mpow(x,n/2);
    return t*t;
}
int main(){
    string st;
    cin>>st;
    int n=st.size();
    vector<mint> a(n);
    int h1=0;
    REP(i,n){
        if(st[i]=='A'){
            if(i){
                a[i]=a[i-1]+mpow(3,h1);
            }else{
                a[i]=1;
            }
        }else if(st[i]=='?'){
            if(i){
                a[i]=a[i-1]*3+mpow(3,h1);
            }else{
                a[i]=1;
            }
            h1++;
        }else{
            if(i){
                a[i]=a[i-1];
            }else{
                a[i]=0;
            }
        }
    }
    int h2=0;
    vector<mint> c(n);
    REPR(i,n-1){
        if(st[i]=='C'){
            if(i<n-1){
                c[i]=c[i+1]+mpow(3,h2);
            }else{
                c[i]=1;
            }
        }else if(st[i]=='?'){
            if(i<n-1){
                c[i]=c[i+1]*3+mpow(3,h2);
            }else{
                c[i]=1;
            }
            h2++;
        }else{
            if(i<n-1){
                c[i]=c[i+1];
            }else{
                c[i]=0;
            }
        }
    }
    
    mint ans=0;
    FOR(i,1,n-1){
        if(st[i]=='B'||st[i]=='?'){
            ans+=a[i-1]*c[i+1];
        }
    }
    cout<<ans<<endl;
    return 0;
}

Measured memory_bytes: 1280