Submission #1085965

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085965		RiverFlow	Railway Trip 2 (JOI22_ho_t4)	C++14	19 / 100	134 ms	38436 KiB

Main

#include <bits/stdc++.h>

#define nl "\n"
#define no "NO"
#define yes "YES"
#define fi first
#define se second
#define vec vector
#define task "main"
#define _mp make_pair
#define ii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define evoid(val) return void(std::cout << val)
#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FOD(i, b, a) for(int i = (b); i >= (a); --i)
#define unq(x) sort(all(x)); x.resize(unique(all(x)) - x.begin())

using namespace std;

template<typename U, typename V> bool maxi(U &a, V b) {
    if (a < b) { a = b; return 1; } return 0;
}
template<typename U, typename V> bool mini(U &a, V b) {
    if (a > b or a == -1) { a = b; return 1; } return 0;
}

const int N = (int)2e5 + 9;
const int mod = (int)1e9 + 7;

void prepare(); void main_code();

int main() {
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    const bool MULTITEST = 0; prepare();
    int num_test = 1; if (MULTITEST) cin >> num_test;
    while (num_test--) { main_code(); }
}

void prepare() {};

int n, k, m, q;
int a[N], b[N];
pair<int, int> Q[N];

namespace SUB1 {
const int N = 307;

int d[N][N];

void sol() {
    memset(d, -1, sizeof d);
    FOR(i, 1, m) {
        if (a[i] < b[i]) {
            FOR(j, a[i], min(a[i] + k - 1, b[i] - 1))
            FOR(t, j + 1, b[i])
                d[j][t] = 1;
        } else {
            FOD(j, a[i], max(a[i] - k + 1, b[i] + 1))
            FOD(t, j - 1, b[i])
                d[j][t] = 1;
        }
    }
    FOR(k, 1, n)
    FOR(i, 1, n) if (d[i][k] != -1)
    FOR(j, 1, n) if (d[k][j] != -1) {
        mini(d[i][j], d[i][k] + d[k][j]);
    }
    FOR(i, 1, q) cout << d[Q[i].fi][Q[i].se] << nl;
}
};

namespace SUB2 {

int l[N], r[N], d[N];
vector<int> insmax[N], revmax[N], insmin[N], revmin[N];

void sol() {
    FOR(i, 1, n) l[i] = n + 1;
    FOR(i, 1, m) {
        if (a[i] < b[i]) {
            insmax[a[i]].push_back(b[i]);
            revmax[min(a[i] + 1 - 1, b[i] - 1)].push_back(b[i]);
        } else {
            insmin[a[i]].push_back(b[i]);
            revmin[max(a[i] - k + 1, b[i] + 1)].push_back(b[i]);
        }
    }
    multiset<int> v;
    FOR(i, 1, n) {
        for(int j : insmax[i]) {
            v.insert(j);
        }
        if (sz(v)) r[i] = *v.rbegin();
        for(int j : revmax[i]) {
            v.erase(v.find(j));
        }
    }
    FOD(i, n, 1) {
        for(int j : insmin[i]) {
            v.insert(j);
        }
        if (sz(v)) l[i] = *v.begin();
        for(int j : revmin[i]) {
            v.erase(v.find(j));
        }
    }
    FOR(i, 1, q) {
        queue<int> f;
        int x = Q[i].fi, y = Q[i].se;
        int L = x, R = x;
        FOR(i, 1, n) d[i] = -1;
        d[x] = 0;
        f.push(x);
        while (!f.empty()) {
            int u = f.front(); f.pop();
            if (u == y) break ;
            if (l[u] < L) {
                FOR(j, l[u], L - 1) {
                    d[j] = d[u] + 1;
                    f.push(j);
                }
                L = l[u];
            }
            if (r[u] > R) {
                FOR(j, R + 1, r[u]) {
                    d[j] = d[u] + 1;
                    f.push(j);
                }
                R = r[u];
            }
        }
        cout << d[y] << nl;
    }
}
};
void main_code() {
    cin >> n >> k >> m;
    for(int i = 1; i <= m; ++i) {
        cin >> a[i] >> b[i];
    }
    cin >> q;
    for(int i = 1; i <= q; ++i) {
        cin >> Q[i].fi >> Q[i].se;
    }
    if (n <= 300 and m <= 300) {
        return SUB1::sol(), void();
    }
    if (max(n, max(m, q)) <= 2000 or q == 1) {
        return SUB2::sol(), void();
    }

}


/*     Let the river flows naturally     */

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:36:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 0 / 8
• Subtask 3: 11 / 11
• Subtask 4: 0 / 25
• Subtask 5: 0 / 35
• Subtask 6: 0 / 13