Submission #205062

# Submission time Handle Problem Language Result Execution time Memory
205062 2020-02-27T20:20:28 Z toxic_hack Priglavci (COCI18_priglavci) C++14
160 / 160
47 ms 2296 KB
// g++ -std=c++14

/*

Today might be the chance to grasp the chance to let your talent bloom.
May be tomorrow, the day after, or next year...
May be even when you are 30. I'm not sure if physique has anything to do with it
but if you think that it will never come, it probably never will.

- Tooru Oikawa.

*/


#include<bits/stdc++.h>

typedef long long ll;
typedef long double lld;
using namespace std;

#define endl "\n"
#define fi first
#define se second
#define pb(x) push_back(x)
#define mp(x,y) make_pair(x,y)
#define MEMS(a,b) memset(a,b,sizeof(a))
#define _ ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define __ freopen("input.txt","r",stdin);freopen("output.txt","w",stdout);
#define all(c) c.begin(),c.end()
#define pii pair<int, int>
#define tr(...) cout<<__FUNCTION__<<' '<<__LINE__<<" = ";trace(#__VA_ARGS__, __VA_ARGS__)
template<typename S, typename T>
ostream& operator<<(ostream& out,pair<S,T> const& p){out<<'('<<p.fi<<", "<<p.se<<')';return out;}

template<typename T>
ostream& operator<<(ostream& out,vector<T> const& v){
ll l=v.size();for(ll i=0;i<l-1;i++)out<<v[i]<<' ';if(l>0)out<<v[l-1];return out;}

template <typename T>
ostream &operator<<(ostream &out, set<T> const &v) {
    for (auto i = v.begin(); i != v.end(); i++)
        out << (*i) << ' ';
    return out;
}
template <typename T, typename V>
ostream &operator<<(ostream &out, map<T, V> const &v) {
    for (auto i = v.begin(); i != v.end(); i++)
        out << "\n" << (i->first) <<  ":"  << (i->second);
    return out;
}

template<typename T>
void trace(const char* name, T&& arg1){cout<<name<<" : "<<arg1<<endl;}

template<typename T, typename... Args>
void trace(const char* names, T&& arg1, Args&&... args){
const char* comma = strchr(names + 1, ',');cout.write(names, comma-names)<<" : "<<arg1<<" | ";trace(comma+1,args...);}

// #define int ll
// v^2sqrt(E)
struct edge
{
	ll from, to, cap, flow, index;
	edge(ll from, ll to, ll cap, ll flow, ll index):
		from(from), to(to), cap(cap), flow(flow), index(index) {}
};

struct PushRelabel
{
	ll n;
	vector<vector<edge> > g;
	vector<long long> excess;
	vector<ll> height, active, count;
	queue<ll> Q;

	PushRelabel(ll n):
		n(n), g(n), excess(n), height(n), active(n), count(2*n) {}

	void addEdge(ll from, ll to, ll cap)
	{
		g[from].push_back(edge(from, to, cap, 0, g[to].size()));
		if(from==to)
			g[from].back().index++;
		g[to].push_back(edge(to, from, 0, 0, g[from].size()-1));
	}

	void enqueue(ll v)
	{
		if(!active[v] && excess[v] > 0)
		{
			active[v]=true;
			Q.push(v);
		}
	}

	void push(edge &e)
	{
		ll amt=(ll)min(excess[e.from], (long long)e.cap - e.flow);
		if(height[e.from]<=height[e.to] || amt==0)
			return;
		e.flow += amt;
		g[e.to][e.index].flow -= amt;
		excess[e.to] += amt;
		excess[e.from] -= amt;
		enqueue(e.to);
	}

	void relabel(ll v)
	{
		count[height[v]]--;
		ll d=2*n;
		for(auto &it:g[v])
		{
			if(it.cap-it.flow>0)
				d=min(d, height[it.to]+1);
		}
		height[v]=d;
		count[height[v]]++;
		enqueue(v);
	}

	void gap(ll k)
	{
		for(ll v=0;v<n;v++)
		{
			if(height[v]<k)
				continue;
			count[height[v]]--;
			height[v]=max(height[v], n+1);
			count[height[v]]++;
			enqueue(v);
		}
	}

	void discharge(ll v)
	{
		for(ll i=0; excess[v]>0 && i<g[v].size(); i++)
			push(g[v][i]);
		if(excess[v]>0)
		{
			if(count[height[v]]==1)
				gap(height[v]);
			else
				relabel(v);
		}
	}

	long long max_flow(ll source, ll dest)
	{
		count[0] = n-1;
		count[n] = 1;
		height[source] = n;
		active[source] = active[dest] = 1;
		for(auto &it:g[source])
		{
			excess[source]+=it.cap;
			push(it);
		}

		while(!Q.empty())
		{
			ll v=Q.front();
			Q.pop();
			active[v]=false;
			discharge(v);
		}

		long long max_flow=0;
		for(auto &e:g[source])
			max_flow+=e.flow;

		return max_flow;
	}
};

int solve() {
    int n, m, c, k;
    cin >> n >> m >> c >> k;
    vector<pii> stud, stop;
    for (int i = 0; i < n; i++) {
        int x, y;
        cin >> x >> y;
        stud.push_back({x, y});
    }
    for (int i = 0; i < m; i++) {
        int x, y;
        cin >> x >> y;
        stop.push_back({x, y});
    }
    vector<vector<int>> buses;
    for (int i = 0; i < k; i++) {
        int ki;
        cin >> ki;
        vector<int> temp;
        for (int j = 0; j < ki; j++) {
            int x;
            cin >> x; x--;
            temp.push_back(x);
        }
        buses.push_back(temp);
    }

    int l = 0, r = 1e9;
    int mid, ans = -1;
    auto sq = [&](int x) {
        return x * x;
    };
    auto dist = [&](pii a, pii b) {
        return (sq(a.fi - b.fi) + sq(a.se - b.se));
    };
    PushRelabel ansIthink(2 + n + m + k);
    while (l <= r) {
        mid = (l + r) / 2;
        PushRelabel flow(2 + n + m + k);
        for (int i = 0; i < n; i++) {
            flow.addEdge(0, 2 + i, 1);
        }

        for (int i = 0; i < k; i++) {
            flow.addEdge(2 + n + m + i, 1, c);
        }

        for (int i = 0; i < k; i++) {
            for (auto j : buses[i]) {
                flow.addEdge(2 + n + j, 2 + n + m + i, c);
            }
        }

        // tr(l, r, mid);
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                // tr(i, j);
                if (dist(stud[i], stop[j]) <= mid) {
                    flow.addEdge(2 + i, 2 + n + j, 1);
                }
            }
        }

        int mxflow = flow.max_flow(0, 1);

        if (mxflow == n) {
            ans = mid;
            ansIthink = flow;
            r = mid - 1;
        } else {
            l = mid + 1;
        }
    }

    if (ans == -1) {
        cout << ans << endl;
    } else {
        cout << ans << endl;
        for (int i = 0; i < n; i++) {
            for (auto e : ansIthink.g[2 + i]) {
                if (e.flow == 1) {
                    cout << e.to - 2 - n + 1 << endl;
                    break;
                }
            }
        }
    }
    return 0;
}

int32_t main(){ _
    int t;
    // cin >> t;
    t = 1;
    while (t--) solve();
}

Compilation message

priglvaci.cpp: In member function 'void PushRelabel::discharge(ll)':
priglvaci.cpp:137:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(ll i=0; excess[v]>0 && i<g[v].size(); i++)
                              ~^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 14 ms 1272 KB Output is correct
2 Correct 14 ms 1144 KB Output is correct
3 Correct 47 ms 940 KB Output is correct
4 Correct 25 ms 2040 KB Output is correct
5 Correct 24 ms 1912 KB Output is correct
6 Correct 15 ms 1272 KB Output is correct
7 Correct 12 ms 760 KB Output is correct
8 Correct 10 ms 1144 KB Output is correct
9 Correct 13 ms 1272 KB Output is correct
10 Correct 19 ms 2296 KB Output is correct