Submission #1233836

#	Time	Username	Problem	Language	Result	Execution time	Memory
1233836		thelegendary08	Swapping Cities (APIO20_swap)	C++17	0 / 100	276 ms	72896 KiB

swap

#include "swap.h"
#include<bits/stdc++.h>
#define int long long
#define mp make_pair
#define pb push_back
#define f0r(i,n) for(signed i = 0; i<n; i++)
#define FOR(i, k, n) for(signed i = k; i<n; i++)
#define vi vector<int>
#define vpii vector<pair<int,int>>
#define pii pair<int,int>
#define vb vector<bool>
#define mii map<int,int>
#define vvi vector<vector<int>>
#define vout(v) for(auto u : v)cout<<u<<' '; cout<<endl;
#define dout(a) cout<<a<<' '<<#a<<endl;
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<endl;
using namespace std;
struct edge{
	int u, v, w;
};
vector<vpii> adj;
int n,m;
vector<vi>edges;
struct DSU{
	int n; vi par, sz, hasthree, hascyc, rep;
	vi treepar, treesz, treea, treeb, weight, dep;
	vvi adj;
	int node_count;
	int m, lg; vvi jmp;
	DSU(){
		
	}
	DSU(int N){
		n = N; node_count = n;
		par.resize(n); sz.resize(n); hasthree.resize(n); hascyc.resize(n);
		f0r(i,n){
			par[i] = i; sz[i] = 1; hasthree[i] = 0; hascyc[i] = 0; rep.pb(i);
			treepar.pb(-1); treesz.pb(1); treea.pb(0); treeb.pb(0); weight.pb(0);
		}
	}
	int find(int x){
		while(x != par[x])x = par[x];
		return x;
	}
	void unite(int a, int b, int w){
		// dout2(a,b);
		a = find(a); b = find(b);
		if(a == b){
			// dout(rep[a]);
			treepar[rep[a]] = node_count;
			treepar.pb(-1);
			treesz.pb(sz[a]);
			treea.pb(treea[a]);
			weight.pb(w);
			treeb.pb(1);
			rep[a] = node_count;
			node_count++;
			hascyc[a] = 1;			
			// vout(treepar);	
			return;
		}
		if(sz[a] < sz[b])swap(a,b);
		treepar[rep[a]] = node_count;
		treepar[rep[b]] = node_count;
		treepar.pb(-1);
		treesz.pb(sz[a] + sz[b]);
		treea.pb(hascyc[a] | hascyc[b]);
		treeb.pb(hasthree[a] | hasthree[b]);
		weight.pb(w);
		rep[a] = node_count;
		sz[a] += sz[b];
		par[b] = a;
		hascyc[a] |= hascyc[b];
		hasthree[a] |= hasthree[b];
		node_count++;
		// vout(treepar);
	}
	
	void build_jmp(){
		m = node_count;
		jmp.resize(m);
		lg = 0;
		for(int i = 62; i>=0; i--){
			if((1LL << i) & m){
				lg = i; break;
			}
		}
		lg++;
		f0r(i,m){
			jmp[i].resize(lg);
		}
		f0r(i,m){
			jmp[i][0] = treepar[i];
		}
		// vout(treepar);
		
		FOR(i, 1, lg){
			f0r(j, m){
				if(jmp[j][i-1] == -1)jmp[j][i] = -1;
				else jmp[j][i] = jmp[jmp[j][i-1]][i-1];
			}
		}
		
		
		adj.resize(m);
		f0r(i,m){
			if(treepar[i] != -1)adj[treepar[i]].pb(i);
		}
		dep.resize(m);
		queue<int>q;
		q.push(m-1);
		while(!q.empty()){
			int node = q.front(); q.pop();
			for(auto u : adj[node]){
				q.push(u); 
				dep[u] = dep[node] + 1;
			}
		}
		
	}
	
	int lca(int a, int b){
		if(dep[a] > dep[b])swap(a,b);
		int dif = dep[b] - dep[a];
		f0r(i, lg){
			if((1LL << i) & dif){
				b = jmp[b][i];
			}
		}
		for(int i = lg - 1; i>=0; i--){
			if(jmp[a][i] != jmp[b][i]){
				a = jmp[a][i]; b = jmp[b][i];
			}
		}
		return treepar[a];
	}
	
	int firstcan(int x){
		if(treea[x] || treeb[x])return x;
		for(int i = lg-1; i>=0; i--){
			if(!(treea[jmp[x][i]] || treeb[jmp[x][i]])){
				x = jmp[x][i];
			}
		}
		x = treepar[x];
		return x;
	}
	
};
vi dist;
int l2;
DSU d = DSU();
void init(signed N, signed M,
          std::vector<signed> U, std::vector<signed> V, std::vector<signed> W) {
    n = N; m = M;
	adj.resize(N); dist.resize(n);
	dist[0] = 4e18;
	f0r(i, M){
		edges.pb({W[i], U[i], V[i]});
		adj[U[i]].pb(mp(V[i], W[i]));
		adj[V[i]].pb(mp(U[i], W[i]));
		dist[V[i]] = W[i];
	}
	sort(edges.begin(), edges.end());
	d = DSU(n);
	f0r(i, M){
		d.unite(edges[i][1], edges[i][2], edges[i][0]);
	}
	d.build_jmp();
}

signed getMinimumFuelCapacity(signed X, signed Y) {
	if(n <= 3)return -1;
	// return 0;
	int l = d.lca(X, Y);
	return d.weight[d.firstcan(l)];
	/*
	vi deg(n);
	DSU d = DSU(n);
	f0r(i, m){
		d.unite(edges[i][1], edges[i][2]);
		deg[edges[i][1]]++;
		deg[edges[i][2]]++;
		int x = d.find(X);
		int y = d.find(Y);
		if(deg[edges[i][1]] == 3){
			d.hasthree[d.find(edges[i][1])] = 1;
		}
		if(deg[edges[i][2]] == 3){
			d.hasthree[d.find(edges[i][2])] = 1;
		}
		if(x == y && (d.hasthree[x] || d.hascyc[x])){
			return edges[i][0];
		}
	}
	return -1;
	*/
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 7
• Subtask 3: 0 / 17
• Subtask 4: 0 / 20
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27