#include <bits/stdc++.h>

const double PI = 3.14159265358979323846;
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
#define rep(i, n) for (int i = 0; i < (n); ++i)
//#define rep(i, n) for (ll i = 0; i < (n); ++i)
//typedef pair<ll, ll> P;
const ll INF = 10e17;
#define cmin(x, y) x = min(x, y)
#define cmax(x, y) x = max(x, y)
#define ret() return 0;

std::istream &operator>>(std::istream &in, set<ll> &o) {
    ll a;
    in >> a;
    o.insert(a);
    return in;
}

std::istream &operator>>(std::istream &in, queue<int> &o) {
    ll a;
    in >> a;
    o.push(a);
    return in;
}


bool contain(set<int> &s, int a) { return s.find(a) != s.end(); }

//ifstream myfile("C:\\Users\\riku\\Downloads\\0_00.txt");
//ofstream outfile("log.txt");
//outfile << setw(6) << setfill('0') << prefecture << setw(6) << setfill('0') << rank << endl;
// std::cout << std::bitset<8>(9);

//const ll mod = 1e10;
//typedef priority_queue<P, vector<P>, greater<P> > PQ_ASK;
class CumulativeSum {
    vector<ll> numbers;
    vector<ll> sums;

public:
    CumulativeSum(int n) {
        numbers.resize(n);
        sums.resize(n);
    }

    void set(int i, ll value) {
        numbers[i] = value;
    }

    ll getSum(int i) {
        if (i == -1) return 0;
        if (i == sums.size()) return sums.back();
        return sums[i];
    }

    ll getSectionSum(int start, int end) {
        return getSum(end) - getSum(start - 1);
    }

    void calculate() {
        for (int i = 0; i < numbers.size(); i++) {
            sums[i] = getSum(i - 1) + numbers[i];
        }
    }

};

const int mod = 1000000007;

struct mint {
    ll x; // typedef long long ll;
    mint(ll x = 0) : x((x % mod + mod) % mod) {}

    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 {
        mint res(*this);
        return res += a;
    }

    mint operator-(const mint a) const {
        mint res(*this);
        return res -= a;
    }

    mint operator*(const mint a) const {
        mint res(*this);
        return res *= a;
    }

    mint pow(ll t) const {
        if (t == -1) return 0;
        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 {
        mint res(*this);
        return res /= a;
    }

    friend std::istream &operator>>(std::istream &in, mint &o) {
        ll a;
        in >> a;
        o = a;
        return in;
    }

    friend std::ostream &operator<<(std::ostream &out, const mint &o) {
        out << o.x;
        return out;
    }

};

int main() {
    string s;
    cin >> s;
    int n = s.size();
    CumulativeSum as(n), bs(n), cs(n), qs(n);
    rep(i, n) {
        char c = s[i];
        if (c == 'A') as.set(i, 1);
        if (c == 'B') bs.set(i, 1);
        if (c == 'C') cs.set(i, 1);
        if (c == '?') qs.set(i, 1);
    }

    as.calculate();
    bs.calculate();
    cs.calculate();
    qs.calculate();

    mint ans = 0;
    rep(i, n) {
        char c = s[i];
        if (c == 'B' || c == '?') {

            int lq = qs.getSectionSum(0, i - 1);
            int ac = as.getSectionSum(0, i - 1);
            int rq = qs.getSectionSum(i + 1, n);
            mint cc = cs.getSectionSum(i + 1, n);

            mint l = mint(ac) * mint(3).pow(lq) + mint(3).pow(lq - 1) * lq;
            mint r = mint(cc) * mint(3).pow(rq) + mint(3).pow(rq - 1) * rq;

            mint now = l * r;
            ans += now;
        }
    }
    cout << ans << endl;

}


Measured memory_bytes: 9836