[Shortest path] poj 2387

#include <iostream>#include <stdlib.h>#include <limits.h>#include <string.h>using namespace std;int map[1010][1010];int dis[1010];int n,pos,sum;void init(){ for(int i=0; i<1001; i++) {  for(int k=0; k<1001; k++)   map[i][k] = INT_MAX;  map[i][i] = 0; } for(int i=0; i<1001; i++)  dis[i] = INT_MAX; sum = 0;}void Dijkstra(){ int used[1010]; memset(used,0,sizeof(used)); int now = pos; dis[now] = 0; used[now] = 1; for(int i=0; i<n; i++) {  for(int k=1; k<=n; k++)   if( map[now][k] != INT_MAX && dis[now] + map[now][k] < dis[k] )    dis[k] = dis[now] + map[now][k];  int min = INT_MAX;  for(int k=1; k<=n; k++)   if( dis[k] < min && !used[k] )    min = dis[now = k];  used[now] = 1; }}int main(){ int from,to,len,t; init(); cin >> t >> n; pos = n; for(int i=1; i<=t; i++) {  cin >> from >> to >> len;  if( len < map[from][to] )   map[from][to] = map[to][from] = len; } Dijkstra(); cout << dis[1] << endl;return 0;}   #include<iostream>using namespace std;#define MAX 1005const int oo=10000000;int dist[MAX][MAX];int close[MAX];bool used[MAX];int main(){    int N,T,i,j;    int s,e,len;    scanf("%d%d",&T,&N);    memset(dist,0x7f,sizeof(dist));    memset(used,false,sizeof(used));    memset(close,0x7f,sizeof(close));    for(i=1;i<=T;i++)    {        scanf("%d%d%d",&s,&e,&len);        if(dist[s][e]>len)            dist[s][e]=dist[e][s]=len;    }    for(i=2;i<=N;i++)    {        close[i]=dist[1][i];    }    used[1]=true;    for(i=2;i<=N;i++)    {        int min=0;int mlen=oo;        for(j=2;j<=N;j++)        {            if(!used[j]&&close[j]<mlen)            {                min=j,mlen=close[j];            }        }        used[min]=true;        for(j=2;j<=N;j++)        {            if(!used[j]&&dist[min][j]<oo)            {                int temp=dist[min][j]+close[min];                if(temp<close[j])                    close[j]=temp;            }        }    }    printf("%d\n",close[N]);    return 0;}

 

[Shortest path] poj 2387