Submission #968881

#	Time	Username	Problem	Language	Result	Execution time	Memory
968881		sano	Walk (CEOI06_walk)	C++14	0 / 100	336 ms	50108 KiB

walk

#include<iostream>
#include<vector>
#include<queue>
#include<string>
#include<fstream>
#include<algorithm>
#include <iomanip>
#include<map>
#include <set>
#include <math.h>
#define ll long long
#define For(i, n) for(ll i = 0; i < (ll)n; i++)
#define ffor(i, a, n) for(ll i = (ll)a; i < (ll)n; i++)
#define rfor(i, n) for(ll i = (ll)n; i >= (ll)0; i--)
#define rffor(i, a, n) for(ll i = (ll)n; i >= (ll)a; i--)
#define vec vector
#define ff first
#define ss second
#define pb push_back
#define pii pair<ll, ll>
#define NEK 1000000
#define mod (1e9 + 7)
#define rsz resize
#define prv 4
#define D 8
using namespace std;

struct budova {
    vec<ll> x;
    vec<ll> y;
    ll ind;
};

struct udalost {
    ll y, x, ind, typ;
};

bool zorad_udalosti(udalost a, udalost b) {
    if (a.y == b.y) {
        return a.x < b.x;
    }
    return a.y < b.y;
}

bool zorad_obdlzniky(budova a, budova b) {
    return a.x[0] < b.x[0];
}

ll dist(pii a, pii b) {
    return abs(a.first - b.first) + abs(a.second - b.second);
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    pii finish;
    cin >> finish.ff >> finish.ss;
    ll n;
    cin >> n;
    vec<budova> p;
    vec<budova> p_pov;
    vec<udalost> p2;
    For(i, n) {
        ll x1, y1, x2, y2;
        cin >> x1 >> y1 >> x2 >> y2;
        if (y1 < y2) swap(y1, y2);
        if (x1 > x2) swap(x1, x2);
        p_pov.pb({ { x1, x2 }, { y1, y2 }, i });
        p.push_back({ {x1, x2}, {y1, y2}, i });
        p2.push_back({ y2, x2, i, 0});
        p2.push_back({ y1, x2, i, 1 });
        p2.push_back({ y2 - 1, x2 + 1, i, 2 });
        p2.push_back({ y1 + 1, x2 + 1, i, 3 });
    }
    p2.push_back({ finish.ss, finish.ff, n, 2 });
    vec<vec<ll>> next(n + 1, vec<ll>(2, 0));
    sort(p2.begin(), p2.end(), zorad_udalosti);
    set<pii> s;
    For(i, p2.size()) {
        if (p2[i].typ == 0) {
            s.insert({ p2[i].x, p2[i].ind });
        }
        if (p2[i].typ == 1) {
            s.erase({ p2[i].x, p2[i].ind });
        }
        if (p2[i].typ == 2) {
            auto q = s.lower_bound({ p2[i].x, p2[i].ind });
            ll dalsi = -1;
            if (q != s.begin()) {
                q--;
                dalsi = q->second;
            }
            next[p2[i].ind][0] = dalsi;
        }
        if (p2[i].typ == 3) {
            auto q = s.lower_bound({ p2[i].x, p2[i].ind });
            ll dalsi = -1;
            if (q != s.begin()) {
                q--;
                dalsi = q->second;
            }
            next[p2[i].ind][1] = dalsi;
        }
    }
    sort(p.begin(), p.end(), zorad_obdlzniky);
    vec<vec<ll>> dp(n, vec<ll>(2, NEK));
    pii start = { 0, 0 };
    For(i, n) {
        pii roh = { p[i].x[1] + 1, p[i].y[1] - 1 };
        ll o = next[p[i].ind][0];
        if (o == -1) dp[p[i].ind][0] = dist(start, roh);
        else {
            pii roh_1 = { p_pov[o].x[1] + 1, p_pov[o].y[1] - 1 };
            pii roh_2 = { p_pov[o].x[1] + 1, p_pov[o].y[0] + 1 };
            dp[p[i].ind][0] = min(dp[o][0] + dist(roh_1, finish), dp[o][1] + dist(roh_2, finish));
        }
        roh = { p[i].x[1] + 1, p[i].y[0] + 1 };
        o = next[p[i].ind][1];
        if (o == -1) dp[p[i].ind][1] = dist(start, roh);
        else {
            pii roh_1 = { p_pov[o].x[1] + 1, p_pov[o].y[1] - 1 };
            pii roh_2 = { p_pov[o].x[1] + 1, p_pov[o].y[0] + 1 };
            dp[p[i].ind][1] = min((dp[o][0] + dist(roh_1, finish)), (dp[o][1] + dist(roh_2, finish)));
        }
    }
    ll o = next[n][0];
    if (o == -1) {
        ll odp = dist(start, finish);
        cout << odp << '\n';
        return 0;
    }
    pii roh1 = { p_pov[o].x[1] + 1, p_pov[o].y[1] - 1 };
    pii roh2 = { p_pov[o].x[1] + 1, p_pov[o].y[0] + 1 };
    ll d1 = dist(roh1, finish);
    ll d2 = dist(roh2, finish);
    ll odp = min(dp[o][0] + d1, dp[o][1] + d2);
    cout << odp << '\n';
    return 0;
}

• Subtask 1: 0 / 100