Equal Sentences(dp思想)

#include 
#define sc scanf
#define pf printf
using namespace std;

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int, int> PII;
const int N = 2e5 + 10;
const int INF = 0x3f3f3f3f;
const double eps = 1e-7;
const int mod = 1e9 + 7;

int t, n;
int dp[N][2];
string str[N];

void solve()
{
    sc("%d", &n);
    for(int i = 1; i <= n; i++)  cin >> str[i]; dp[1][0] = 1;
    for(int i = 1; i <= n; i++) dp[i][1] = 0;
    for(int i = 2; i <= n; i++){
        dp[i][0] = (dp[i - 1][0] + dp[i - 1][1]) % mod;
        if(str[i] != str[i - 1])  dp[i][1] = dp[i - 1][0];
    }
    pf("%d
", (dp[n][0] + dp[n][1]) % mod);
}

int main()
{
    sc("%d", &t); while(t--) solve();
    return 0;
}