#include <cstdio>

#include <cstring>

#include <cstdlib>

using namespace std;

const int maxn = 10005;

const int INF = 0x3f3f3f3f;

char ch;

int tt;

int vis[10005];

char last;

int main()

{

    int n;

    while(scanf("%d",&n) != EOF)

    {

        int ans = 0;

        int num;

        int i;

        memset(vis,0,sizeof(vis));

        for(i = 1; i <= n; i++)

        {

            getchar();

            scanf("%c",&ch);

            if(ch == 'S')

                ans++;

            else

            {

                scanf("%d",&num);

                if(num == 1)

                    ans ++;

            }

        }

        printf("%d\n",ans);

    }

    return 0;

}