#include <cstdio>
#include <cstring>

const int mod = 1000000007;
inline int plus(const int x, const int y) {return x + y < mod ? x + y : x + y - mod;}
int dp[505][2005], suf[2005], n, m, k;
char s[2005];
bool chk(int a, int b, int c, int d) {return (b - a + 4) % 4 == 1 && (c - b + 4) % 4 == 1 && (d - c + 4) % 4 == 1;}

int main() {
	scanf("%s", s + 1);
	n = strlen(s + 1);
	for (int i = 1; i <= n; ++ i) s[i] -= 'A';
	while (true) {
		int flg = 0;
		for (int i = 1; i + 3 <= n; ++ i) if (chk(s[i], s[i + 1], s[i + 2], s[i + 3])) {flg = i; break;}
		if (!flg) {m = n; break;}
		++ k, n -= 4;
		for (int i = flg; i <= n; ++ i) s[i] = s[i + 4];
	}
	n = m + 4 * k;
	dp[0][m + 1] = 1;
	for (int i = 1; i <= k; ++ i) {
		suf[n + 2] = 0;
		for (int j = n + 1; j; -- j) suf[j] = plus(suf[j + 1], dp[i - 1][j]);
		dp[i][4] = 4ll * suf[1] % mod;
		for (int j = 5; j <= n + 1; ++ j) dp[i][j] = 3ll * suf[j - 3] % mod;
	}
	int ans = 0;
	for (int i = 0; i <= n + 1; ++ i) ans = (ans + dp[k][i]) % mod;
	printf("%d", ans);
	return 0;
}