Submission #938671

#	Time	Username	Problem	Language	Result	Execution time	Memory
938671		faruk	Toll (BOI17_toll)	C++17	0 / 100	116 ms	55124 KiB

toll

#include <bits/stdc++.h>
#define mp make_pair
#define all(a) a.begin(), a.end()

using namespace std;

typedef long long ll;
typedef pair<ll, ll> pii;

vector<vector<pii> > graph;
int k;
vector<ll> combine(vector<ll> beg, int bn, vector<ll> endd) {
    vector<ll> ans(k, 1e18);
    for (int i = 0; i < k; i++)
        for (auto &[to, w] : graph[bn * k + i])
            ans[to] = min(ans[to], beg[i] + endd[to] + w);
    return ans;
}

const int lg = 18;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    int n, m, q;
    cin >> k >> n >> m >> q;
    graph = vector<vector<pii> >(n + 2 * k);
    for (int i = 0; i < m; i++) {
        int f, t, p;
        cin >>f >> t >> p;
        graph[f].push_back(pii(t % k, p));
    }

    vector<vector<vector<ll> > > lift(lg, vector<vector<ll> > (n / k + 1, vector<ll>(k, 1e18)));
    int num_lay = n / k + 1;
    for (int i = 0; i < num_lay; i++)
        lift[0][i] = vector<ll>(k, 0);
    for (int bit = 1; bit < lg; bit++)
        for (int i = num_lay - (1 << bit - 1) - 1; i >= 0; i--) 
            lift[bit][i] = combine(lift[bit - 1][i], i, lift[bit - 1][i + (1 << (bit - 1))]);


    while (q--) {
        int f, t;
        cin >> f >> t;
        int SF = f / k, ST = t / k;
        vector<ll> ans(k, 1e18);
        ans[f % k] = 0;
        int diff = ST - SF;
        for (int i = 0; i < lg; i++) {
            if (((1 << i) & diff) != 0) {
                ans = combine(ans, SF, lift[i][SF + 1]);
                SF += (1 << i);
            }
        }

        if (ans[t % k] == 1e18)
            cout << "-1\n";
        else
            cout << ans[t % k] << "\n";
    }
}

Compilation message (stderr)

toll.cpp: In function 'int main()':
toll.cpp:40:42: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   40 |         for (int i = num_lay - (1 << bit - 1) - 1; i >= 0; i--)
      |                                      ~~~~^~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 10
• Subtask 3: 0 / 8
• Subtask 4: 0 / 31
• Subtask 5: 0 / 44