Submission #100089

#	Time	Username	Problem	Language	Result	Execution time	Memory
100089		lyc	Roller Coaster Railroad (IOI16_railroad)	C++14	0 / 100	325 ms	13036 KiB

railroad

#include "railroad.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
#define FOR(i, a, b) for (int i = a; i <= b; ++i)

const int N = 2e5+5;
int am[16][16];
ll res[16][(1<<16)+5];

ll dp(int i, int bm) {
    if (bm == 0) return 0;
    if (~res[i][bm]) return res[i][bm];

    res[i][bm] = 1e18;
    int x = bm;
    while (x) {
        int lso = x&-x;
        int j = __builtin_ctz(lso);
        res[i][bm] = min(res[i][bm], am[i][j] + dp(j, bm ^ lso));
        x -= lso;
    }
    //cout << i << " " << bm << " :: " << res[i][bm] << endl;
    return res[i][bm];
}

long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
    int n = (int) s.size();
    if (false && n <= 16) {
        FOR(i, 0, n-1) {
            FOR(j, 0, n-1) {
                am[i][j] = max(0, t[i]-s[j]);
            }
        }
        memset(res, -1, sizeof res);
        ll ans = 1e18;
        FOR(i, 0, n-1) ans = min(ans, dp(i, ((1<<n)-1)^(1<<i)));
        return ans;
    }
    else {
        multiset<int> out;
        FOR(i, 0, n-1) {
            out.insert(s[i]);
        }
        out.insert(1e9+10);

        sort(t.begin(), t.end());
        reverse(t.begin(), t.end());
        FOR(i, 0, n-1) {
            auto it = out.lower_bound(t[i]);
            //for (auto x : out) cout << x << " " ; cout << endl;

            if (it == out.end()) return 1;
            else out.erase(it);
        }
        return 0;
    }
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 23
• Subtask 3: 0 / 30
• Subtask 4: 0 / 36