#include <map>
#include <set>
#include <array>
#include <cmath>
#include <deque>
#include <bitset>
#include <random>
#include <string>
#include <vector>
#include <cassert>
#include <complex>
#include <iomanip>
#include <iostream>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>

using namespace std;

const int MOD = 1e9 + 7;

int add(int a, int b) {
    return a + b >= MOD ? a + b - MOD : a + b;
}

int sub(int a, int b) {
    return a >= b ? a - b : a + MOD - b;
}

int mul(int a, int b) {
    return (1ll * a * b) % MOD;
}

bool check(string& s) {
    for (int i = 3; i < (int)s.size(); ++i) {
        bool f = true;
        for (int j = i - 3; j < i; ++j) {
            int ch = (s[j] - 'A' + 1) % 4;
            if (ch + 'A' != s[j + 1]) f = false;
        }
        if (f) {
            string t = s.substr(0, i - 3) + s.substr(i + 1, s.size() - i - 1);
            s = t;
            return true;
        }
    }
    return false;
}


int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    string s;
    cin >> s;

    int n = s.size();
    int k = 0;
    while (check(s)) ++k;

    vector<int> dp(n + 10);
    dp[s.size()] = 1;
    for (int i = 0; i < k; ++i) {
        vector<int> dp1(n + 10);
        for (int i = 3; i <= n; ++i) {
            dp1[i] = mul(dp[i - 3], 3);
        }
        for (int i = n - 1; i >= 3; --i) {
            dp1[i] = add(dp1[i], dp1[i + 1]);
        }
        for (int i = 0; i <= n; ++i) {
            dp1[3] = add(dp1[3], dp[i]);
        }
        dp = dp1;
    }

    int ans = 0;
    for (int x : dp) {
        ans = add(ans, x);
    }

    cout << ans << "\n";

    
    return 0;
}