【題解】Codeforces 1282C. Petya and Exam

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
 
struct prob{
    int l, d;
};
int m, n, t, t_e, t_h, a[200005], b[200000], remain_e, remain_h, s, mx, tmp, cnt, score;
vector <prob> v;
bool cmp(prob x, prob y){
    return x.d < y.d;
}
 
int main() {
    cin >> m;
    while (m--){
        cin >> n >> t >> t_e >> t_h;
        remain_e = 0;
        remain_h = 0;
        for (int i = 0; i < n; i++){
            cin >> a[i];
            if (a[i] == 1) remain_h++;
            else remain_e++;
        }
        v.clear();
        for (int i = 0; i < n; i++){
            cin >> b[i];
            v.push_back({a[i], b[i]});
        }
        v.push_back({0, t+1});
        sort(v.begin(), v.end(), cmp);
        mx = 0;
        s = 0;
        score = 0;
        for (prob i:v){
            if (s > t) break;
            if (s < i.d){
                tmp = i.d-s-1;
                cnt = 0;
                if (remain_e && tmp >= t_e){
                    cnt += min(remain_e, tmp/t_e);
                    tmp -= cnt * t_e;
                }
                if (remain_h && tmp >= t_h){
                    cnt += min(remain_h, tmp/t_h);
                }
                mx = max(mx, score+cnt);
            }
            if (i.l == 0){
                s += t_e;
                remain_e--;
            }
            else{
                s += t_h;
                remain_h--;
            }
            score++;
        }
        cout << mx << "\n";
    }
}