Submission #211393

#	Time	Username	Problem	Language	Result	Execution time	Memory
211393		socho	Crocodile's Underground City (IOI11_crocodile)	C++14	0 / 100	8 ms	6272 KiB

crocodile

#include "crocodile.h"
#include "bits/stdc++.h"
using namespace std;
// #define endl '\n'
// #define int long long

int n, m;
const int MXN = 100005;
vector<pair<int, int> > adj[MXN];
bool ter[MXN], assign[MXN];
int dist[MXN];
int via[MXN];
int gdis[MXN];
priority_queue<pair<int, int>, vector<pair<int, int> >, greater<pair<int, int> > > pro, gpr;

void gdi() {
	for (int i=0; i<MXN; i++) gdis[i] = INT_MAX;
	while (!gpr.empty()) {
		int di = gpr.top().first;
		int no = gpr.top().second;
		gpr.pop();
		if (gdis[no] < di) continue;
		gdis[no] = di;
		for (int i=0; i<adj[no].size(); i++) {
			int o = adj[no][i].first;
			int od = adj[no][i].second + di;
			if (gdis[o] > od) {
				gdis[o] = od;
				gpr.push(make_pair(od, o));
			}
		}
	}
}

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[])
{
  
	n = N, m = M;
	for (int i=0; i<m; i++) {
		int a, b, w;
		a = R[i][0], b = R[i][1], w = L[i];
		adj[a].push_back(make_pair(b, w));
		adj[b].push_back(make_pair(a, w));
	}
	
	int poss[MXN];
	memset(poss, 0, sizeof poss);
	bool done[MXN];
	
	for (int i=0; i<MXN; i++) dist[i] = INT_MAX;
	
	int k = K;
	for (int i=0; i<k; i++) {
		int x = P[i];
		ter[x] = true;
		dist[x] = 0;
		done[x] = true;
		pro.push(make_pair(0, x));
		gpr.push(make_pair(0, x));
	}
	
	gdi();
	
	vector<int> towa[MXN];
	
	while (!pro.empty()) {
		
		
		int di = pro.top().first;
		int no = pro.top().second;
		pro.pop();
		
		if (dist[no] < di) continue; // do not relax

		if (poss[no] >= 2) {
			// can be calculated now
			// but what if more relaxations are pending
			vector<int> ch;
			for (int i=0; i<adj[no].size(); i++) {
				int o = adj[no][i].first;
				if (done[o]) {
					ch.push_back(dist[o] + adj[no][i].second);
				}
			}
			sort(ch.begin(), ch.end());
			dist[no] = ch[1];
			done[no] = true;
		}
		
		if (done[no] && !assign[no]) {
			assign[no] = true;
			for (int i=0; i<adj[no].size(); i++) {
				int o = adj[no][i].first;
				if (!done[o]) {
					poss[o]++;
					towa[o].push_back(dist[no] + adj[no][i].second);
					if (poss[o] >= 2) pro.push(make_pair(gdis[no] + adj[no][i].second, o));
				}
			}
		}

	}
	
	assert(dist[0] != INT_MAX);
	return dist[0];
  
}

Compilation message (stderr)

crocodile.cpp: In function 'void gdi()':
crocodile.cpp:24:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i=0; i<adj[no].size(); i++) {
                 ~^~~~~~~~~~~~~~~
crocodile.cpp: In function 'int travel_plan(int, int, int (*)[2], int*, int, int*)':
crocodile.cpp:79:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i=0; i<adj[no].size(); i++) {
                  ~^~~~~~~~~~~~~~~
crocodile.cpp:92:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i=0; i<adj[no].size(); i++) {
                  ~^~~~~~~~~~~~~~~

• Subtask 1: 0 / 46
• Subtask 2: 0 / 43
• Subtask 3: 0 / 11