#include <iostream>
#include <cstring>
#include <algorithm>
#include <map>

using namespace std;

const int N = 100010;

int n;

int main()
{
    map<int, int> b;
    cin >> n;
    int x = 0;
    while (n -- )
    {
        int y;
        char c;
        cin >> y >> c;
        if (c == 'R')
        {
            b[x] ++ ;
            b[x + y] -- ;
            x += y;
        }
        else
        {
            b[x - y] ++ ;
            b[x] -- ;
            x -= y;
        }
    }
    int res = 0, sum = 0, last;
    for (auto [x, v]: b)
    {
        if (sum >= 2)
            res += x - last;
        sum += v;
        last = x;
    }
    cout << res << endl;
    return 0;
}