Cod sursa(job #631428)

Utilizator DranaXumAlexandru Dumitru Paunoiu DranaXum Data 8 noiembrie 2011 00:35:04
Problema Algoritmul lui Dijkstra Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 3.21 kb
using namespace std;

#include <set>
#include <map>
#include <list>
#include <deque>
#include <stack>
#include <queue>
#include <cmath>
#include <ctime>
#include <cctype>
#include <cstdio>
#include <vector>
#include <string>
#include <bitset>
#include <utility>
#include <iomanip>
#include <fstream>
#include <cstring>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>

#define oo (1<<30)
#define f first
#define s second
#define II inline
#define db double
#define ll long long
#define pb push_back
#define mp make_pair
#define Size(V) ((int)(V.size()))
#define all(V) (V).begin() , (V).end()
#define CC(V) memset((V),0,sizeof((V)))
#define CP(A,B) memcpy((A),(B),sizeof((B)))
#define FOR(i,a,b) for(int (i)=(a);(i)<=(b);++(i))
#define REP(i, N) for (int (i)=0;(i)<(int)(N);++(i))
#define FORit(it, x) for (__typeof((x).begin()) it = (x).begin(); it != (x).end(); ++it)

#define IN "dijkstra.in"
#define OUT "dijkstra.out"
#define N_MAX (1<<17)

typedef vector<int> VI;
typedef pair<int,int> pi;
typedef vector<string> VS;
template<class T> string toString(T n) {ostringstream ost;ost<<n;ost.flush();return ost.str();}

class CompareHeap {
	private:
		vector<ll> pc;
	public:
		CompareHeap(const vector<ll>& pc) {
			this->pc = pc;
		}
		bool operator()(const int x, const int y) const
    {
        return pc[x]  < pc[y] ;
    }
};
class Dijkstra {
	private:
		int source;
		vector<ll> pathCost;
		vector<ll> nodeParent;
		vector<pi> graph[N_MAX];
		int nNode;
		
		void addRec(int dest,VI& path) {
			if(dest==-1)
				return;
			addRec(nodeParent[dest],path);
			path.pb(dest);
		}
	public:
		Dijkstra(int nNode) {
			this->nNode = nNode;
			pathCost = vector<ll>(nNode);
			nodeParent = vector<ll>(nNode);
			FORit(it, pathCost)
				(*it) = oo;
			FORit(it, nodeParent)
				(*it) = -1;
		}
		void addEdge(int src,int dest,int cost) {
			graph[src].pb(mp(dest,cost));
		}
		void addSource(int node) {
			this->source = node;
		}
		ll getMinCost(int dest) {
			return pathCost[dest];
		}
		VI getPathFromSource(int dest) {
			VI rec;
			addRec(dest,rec);
			return rec;
		}
		II void run() {
				vector<int> heap;
				vector<bool> inheap = vector<bool>(nNode);
				pathCost[source] = 0;
				heap.pb(source);
				inheap[source]=true;
				int heapSize = 1;
				CompareHeap heapCompare(pathCost);
				while(heapSize) {
					int node = heap.front();
					pop_heap(heap.begin(),heap.begin()+heapSize,heapCompare);
					heapSize--;
					inheap[node] = false;
					FORit(it,graph[node])
					{
						if(pathCost[(*it).f]>pathCost[node]+(*it).s) {
							pathCost[(*it).f] = pathCost[node]+(*it).s;
							nodeParent[(*it).f]=node;
							if(!inheap[(*it).f]) {
								(*(heap.begin()+heapSize))=(*it).f; heapSize++;
								push_heap(heap.begin(),heap.begin()+heapSize,heapCompare);
							}
							else {
								make_heap(heap.begin(),heap.begin()+heapSize,heapCompare);
							}
						}
					}
				}
		}
		~Dijkstra() {
		}
};

void scan() {
	int N,M;
	freopen(IN,"r",stdin);
	freopen(OUT,"w",stdout);
	scanf("%d%d",&N,&M);
	Dijkstra dij(N+1);
	for(int i=0;i<M;i++) {
		int x,y,c;
		scanf("%d%d%d",&x,&y,&c);
		dij.addEdge(x,y,c);
	}
	dij.addSource(1);
	dij.run();
	FOR(i,2,N)
		printf("%lld ",dij.getMinCost(i));
}
int main()
{
	scan();
	return 0;
}