HDU 2544 最最裸的最短路

Dijkstra + Heap

Problem : 2544 ( 最短路 )     Judge Status : Accepted
RunId : 8360313    Language : G++    Author : CherryChou
Code Render Status : Rendered By HDOJ G++ Code Render Version 0.01 Beta

 

# include<cstdio>

# include<cstring>

# include<algorithm>

# include<queue>

# include<map>

# include<vector>

# include<utility>

using namespace std; const int inf=1<<25; const int maxn=105; const int maxm=20005; typedef pair<int,int> node; struct edge { int u,v,w,next; } e[maxm]; struct cmp { bool operator()(const node &a,const node &b)const { return a.second>b.second; } }; int num,head[maxn]; int dis[maxn],n,m; bool vis[maxn];

priority_queue<node,vector<node>,cmp> q; inline void add(int u,int v,int w) {

    e[num].u=u;

    e[num].v=v;

    e[num].w=w;

    e[num].next=head[u];

    head[u]=num++; } void addedge(int u,int v,int w) {

    add(u,v,w);

    add(v,u,w); } void dijkstra(int s) { int i,u,v;

    dis[s]=0;

    q.push(make_pair(s,dis[s])); while(!q.empty()) {

        u=q.top().first;

        q.pop(); if(vis[u]) continue;

        vis[u]=1; for(i=head[u];i!=-1;i=e[i].next) {

            v=e[i].v; if(!vis[v]&&dis[u]+e[i].w<dis[v]) {

                dis[v]=dis[u]+e[i].w;

                q.push(make_pair(v,dis[v])); } } } } void init() {

    num=0;

    memset(head,-1,sizeof(head));

    memset(vis,0,sizeof(vis)); for(int i=0;i<=n;i++) {

        dis[i]=inf;

        vis[i]=0; } } int main() { while(~scanf("%d%d",&n,&m),n+m) {

        init(); int s,t,w; while(m--) {

            scanf("%d%d%d",&s,&t,&w);

            addedge(s,t,w); }

        dijkstra(1);

        printf("%d\n",dis[n]); } return 0; }

 

 

SPFA

 

Problem : 2544 ( 最短路 )     Judge Status : Accepted
RunId : 8360334    Language : G++    Author : CherryChou
Code Render Status : Rendered By HDOJ G++ Code Render Version 0.01 Beta

 

# include<cstdio>

# include<cstring>

# include<algorithm>

# include<queue>

using namespace std; const int inf=1<<25; const int maxn=105; const int maxm=20005; typedef pair<int,int> node; struct edge { int u,v,w,next; } e[maxm]; int num,head[maxn]; int dis[maxn],n,m; bool vis[maxn];

queue<int> q; inline void add(int u,int v,int w) {

    e[num].u=u;

    e[num].v=v;

    e[num].w=w;

    e[num].next=head[u];

    head[u]=num++; } void addedge(int u,int v,int w) {

    add(u,v,w);

    add(v,u,w); } void spfa(int s) { int i,u,v;

    dis[s]=0;

    q.push(s);

    vis[s]=1; while(!q.empty()) {

        u=q.front();

        q.pop(); for(i=head[u];i!=-1;i=e[i].next) {

            v=e[i].v; if(dis[u]+e[i].w<dis[v]) {

                dis[v]=dis[u]+e[i].w; if(!vis[v]) {    

                        q.push(v);

                    vis[v]=1; } } }

        vis[u]=0; } } void init() {

    num=0;

    memset(head,-1,sizeof(head));

    memset(vis,0,sizeof(vis)); for(int i=1;i<=n;i++) {

        dis[i]=inf;

        vis[i]=0; } } int main() { while(~scanf("%d%d",&n,&m),n+m) {

        init(); int s,t,w; while(m--) {

            scanf("%d%d%d",&s,&t,&w);

            addedge(s,t,w); }

        spfa(1);

        printf("%d\n",dis[n]); } return 0; }