2347eece.cpp

#include <bits/stdc++.h>
#define alive std::cout << "$LINE @" << __LINE__ << " ALIVE" << std::endl
#define watch(var) std::cout << "$ LINE @" << __LINE__ << " FUN @" << __FUNCTION__ \
                             << " VAR @" << (#var) << ": " << (var) << std::endl

using namespace std;

typedef int i32;
typedef unsigned int u32;
typedef long long i64;
typedef unsigned long long u64;
typedef double f64;
typedef long double f128;
typedef pair<int, int> pii;

template <typename Tp>
inline void read(Tp &x)
{
    x = 0;
    bool neg = false;
    char c = getchar();
    for (; !isdigit(c); c = getchar())
    {
        if (c == '-')
        {
            neg = true;
        }
    }
    for (; isdigit(c); c = getchar())
    {
        x = x * 10 + c - '0';
    }
    if (neg)
    {
        x = -x;
    }
}

const int M = 1e5 + 5;

int main()
{
    int n, w, u, v, s, e;
    read(n), read(w), read(u), read(v), read(s), read(e);

    const f64 W = (f64)w, U = (f64)u, V = (f64)v, S = (f64)s, E = (f64)e;
    vector<pair<f64, int>> vec;
    vec.reserve(M);
    vec.emplace_back(S, 0);
    vec.emplace_back(E, 0);

    char op[5];
    f64 L, R;

    for (int i = 0, dir, m; i < n; ++i)
    {
        scanf("%s", op);
        dir = (op[0] == 'W') ? 1 : -1;
        read(m);
        for (int k = 0, l, p; k < m; ++k)
        {
            read(l), read(p);
            L = std::max((f64)dir * (f64)p / U - W * (f64)(i + 1) / V, S);
            R = std::min(((f64)dir * (f64)p + (f64)l) / U - W * (f64)i / V, E);
            if (L <= E && R >= S)
            {
                vec.emplace_back(L, 1);
                vec.emplace_back(R, -1);
            }
        }
    }

    sort(vec.begin(), vec.end());

    f64 ans = 0.0;
    int cur = 0;

    for (size_t i = 0UL, len = vec.size() - 1UL; i < len; ++i)
    {
        cur += vec[i].second;
        if (cur == 0)
        {
            ans = std::max(ans, vec[i + 1UL].first - vec[i].first);
        }
    }

    printf("%.8f\n", ans);
    return 0;
}