Submission #1085870

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085870		DaciejMaciej	Robot (JOI21_ho_t4)	C++17	0 / 100	201 ms	39100 KiB

Main

#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// #include <ext/rope>

using namespace std;
// using namespace __gnu_pbds;

typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int uint;
typedef long double ld;

template <class T>

using VV = vector<vector<T>>;

using VI = vector<int>;
using VVI = vector<vector<int>>;

using VL = vector<long long>;
using VVL = vector<vector<long long>>;

using VC = vector<char>;
using VVC = vector<vector<char>>;

using VB = vector<bool>;
using VVB = vector<vector<bool>>;

using VD = vector<double>;
using VVD = vector<vector<double>>;

using PII = pair<int, int>;
using PLL = pair<long long, long long>;
using PIL = pair<int, long long>;
using PLI = pair<long long, int>;

using VPII = vector<pair<int, int>>;
using VPLL = vector<pair<long long, long long>>;

#define LINE '\n'
#define SPACE ' '
#define PB push_back
#define FOR(i, a, b) for (int i = (a); i < (int(b)); i++)
#define FORE(i, a, b) for (int i = (a); i <= (int)((b)); i++)
#define ALL(x) x.begin(), x.end()
#define RALL(x) x.rbegin(), x.rend()
#define sq(a) ((a) * (a))
#define sz(x) ((int)s.size())

// zero indexed
template <class T>
struct segtree
{
    const T def = 0;
    int n;
    vector<T> seg;

    segtree(int _size) : n(_size), seg(2 * _size, def) {}

    T merge(T a, T b)
    {
        return max(a, b);
    }
    void update(int pos, T val)
    {
        for (seg[pos += n] = val; pos /= 2;)
        {
            seg[pos] = merge(seg[pos * 2], seg[pos * 2 + 1]);
        }
    }
    T query(int l, int r)
    { // get [l, r]
        T a = def, b = def;
        for (l += n, r += n + 1; l < r; l /= 2, r /= 2)
        {
            if (l % 2)
                a = merge(a, seg[l++]);
            if (r % 2)
                b = merge(b, seg[--r]);
        }
        return merge(a, b);
    }
};

const ll MOD = 1e9 + 7;

template <class T>
void maxi(T &a, T b)
{
    a = max(a, b);
}

template <class T>
void mini(T &a, T b)
{
    a = min(a, b);
}

template <class T>
void addi(T &a, T b)
{
    a = (a + b) % MOD;
}

template <class T>
void subi(T &a, T b)
{
    a = (a - b + MOD) % MOD;
}

template <class T>
T add(T a, T b)
{
    return (a + b) % MOD;
}

template <class T>
T sub(T a, T b)
{
    return (a - b + MOD) % MOD;
}

template <class T>
T mul(T a, T b)
{
    return ((a % MOD) * (b % MOD)) % MOD;
}

ll binpow(ll a, ll b, ll mod)
{
    ll res = 1;
    while (b > 0)
    {
        if (b & 1)
        {
            res = (res * a) % mod;
        }
        a = (a * a) % mod;
        b >>= 1;
    }

    return res;
}

struct DSU
{

    VI par;
    VI size;
    DSU(int _n) : par(_n), size(_n, 1)
    {
        iota(ALL(par), 0);
    }

    bool merge(int x, int y)
    {
        x = find(x);
        y = find(y);

        if (x == y)
            return false;
        if (size[y] > size[x])
            swap(x, y);
        size[x] += size[y];
        par[y] = x;
        return true;
    }

    int find(int x)
    {
        return (par[x] == x ? x : par[x] = find(par[x]));
    }

    bool connected(int x, int y)
    {
        return find(x) == find(y);
    }

    void reset()
    {
        FOR(i, 0, par.size())
        par[i] = i,
        size[i] = 1;
    }
};

const int INF = 1e9;

const int MAX_N = 1e5 + 3;

int n, m;
struct Edge
{
    int to;
    int c;
    ll p;
};

struct State
{
    ll cost;
    int node;
    int color;
    Edge backEdge;

    bool operator>(const State &other) const
    {
        return cost > other.cost;
    }
};

vector<Edge> g[MAX_N];

map<int, ll> psum[MAX_N];
VVL dp(MAX_N, VL(2, 1e17));
map<int, ll> dp2[MAX_N];
// 0 - came from unique edge
// came from uncolored edge


/*
TO:DO - fix case1 and case2, beacuse comming from another color might cause better answear
 so keep just do[node][c] as the minimum of comming to node via edge c

*/
void solve()
{
    cin >> n >> m;

    FOR(i, 0, m)
    {
        int a, b, c, p;
        cin >> a >> b >> c >> p;

        g[a].PB({b, c, p});
        g[b].PB({a, c, p});
        psum[a][c] += p;
        psum[b][c] += p;
    }

    priority_queue<State, vector<State>, greater<State>> pq;
    dp[1][0] = 0;

    pq.push({0, 1, 0, {0, -1, 0}});
    while (!pq.empty())
    {
        auto [cost, node, color, back_edge] = pq.top();
        //cerr << "cost=" << cost << " nd=" << node << " c=" << color << " dp=" << min(dp[node][0], dp[node][1]) << LINE;
        pq.pop();
       
        for (auto e : g[node])
        {
            //cerr << "AT e: to=" << e.to << " c=" << e.c << " p=" << e.p << LINE;
            if (color == 0)
            {
                // came from any and repaint rest color e.c
                ll case1 = cost + psum[node][e.c] - e.p;
                if(e.c == back_edge.c) case1 -= back_edge.p;

                //cerr << "case1= " << case1 << LINE;
                if (!dp2[e.to].count(e.c) || case1 < dp2[e.to][e.c])
                {
                    dp[e.to][1] = case1;
                    dp2[e.to][e.c] = case1;
                    pq.push({case1, e.to, e.c, e});
                }
            }
            else
            {
                if (e.c != color) // possibly can pass using e
                {
                    ll case2 = cost + psum[node][e.c] - e.p;
                    //cerr << "case2= " << case2 << LINE;

                    if (!dp2[e.to].count(e.c) || case2 < dp2[e.to][e.c])
                    {
                        dp[e.to][1] = case2;
                        dp2[e.to][e.c] = case2;
                        pq.push({case2, e.to, e.c, e});
                    }
                }
            }

            // universal: just repaint e to unique color
            ll case3 = cost + e.p;
            //cerr << "case3= " << case3 << LINE;
            if (case3 <= dp[e.to][0])
            {
                dp[e.to][0] = case3;
                pq.push({case3, e.to, 0, e});
            }
        }
        //cerr << LINE;
    }
    ll ans = min(dp[n][0], dp[n][1]);

    cout << (ans < 1e17 ? ans : -1)  << LINE;
}

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

    int t = 1;
    // cin >> t;

    while (t--)
        solve();
}

• Subtask 1: 0 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42