// yukicoder: No.663 セルオートマトンの逆操作
// bal4u 2019.8.14

#include <stdio.h>

#if 1
#define gc() getchar_unlocked()
#else
#define gc() getchar()
#endif

int in() {   // 非負整数の入力
	int n = 0, c = gc();
	do n = 10 * n + (c & 0xf); while ((c = gc()) >= '0');
	return n;
}

#define MOD 1000000007
int N;
char e[2002];
int dp[2002][2][2];
int a[4][2] = {{0,0},{0,1},{1,0},{1,1}};

int main()
{
	int i, j, ans;
	
	N = in();
	for (i = 0; i < N; i++) e[i] = gc() & 1, gc();
	ans = 0;
	for (j = 0; j < 4; j++) {
		dp[0][0][0] = dp[0][0][1] = dp[0][1][0] = dp[0][1][1] = 0;
		dp[0][a[j][0]][a[j][1]] = 1;
		if (dp[0][0][1] && e[0] == 0) continue;
		for (i = 1; i <= N; i++) {
			if (e[i-1]) {
				dp[i][1][0] = (dp[i-1][0][1] + dp[i-1][1][1]) % MOD;
				dp[i][0][1] = (dp[i-1][0][0] + dp[i-1][1][0]) % MOD;
				dp[i][1][1] = dp[i-1][0][1];
			} else {
				dp[i][0][0] = (dp[i-1][0][0] + dp[i-1][1][0]) % MOD;
				dp[i][1][1] = dp[i-1][1][1];
			}
		}
		ans = (ans + dp[N][a[j][0]][a[j][1]]) % MOD;
	}
	printf("%d\n", ans);
	return 0;
}