1 //prev[],dist[],distance[][]
 2 #include<iostream>
 3 #include<stdio.h>
 4 #include<limits.h>
 5 using namespace std;
 6 const int MAX = 100;
 7 int c[MAX][MAX];
 8 int dist[MAX];
 9 int prev[MAX];
10 int S[MAX];
11 void dijkstra(int s,int n,int dist[],int prev[],int c[][MAX])
12 {
13     for(int i = 1; i <= n; i++)//数组下标都从1开始
14     {
15     dist[i] = c[s][i];
16     S[i] = 0;//0代表，i不再S集合中
17     if(i != s && dist[i] < INT_MAX)
18         prev[i] = s;//i的前一个节点
19     else
20         prev[i] = -1;//prev数组初始化
21     }
22     S[s] = 1;//源点s放在结合S中
23     //选择不在S集合中的具有最短距离的顶点u
24     int u;
25     for(int i = 1; i < n; i++)
26     {
27         int mindis = INT_MAX;
28     for(int j = 1; j <= n; j++)
29     {
30         if(!S[j] && dist[j] < mindis)
31         {
32         u = j;
33         mindis = dist[j];
34         }
35     }
36     S[u] = 1;
37     for(int k = 1; k <= n; k++)
38     {
39         if(!S[k] && c[u][k] < INT_MAX && dist[u] + c[u][k] < dist[k])
40         {
41             dist[k] = dist[u] + c[u][k];
42             prev[k] = u;
43         }
44     }
45     }
46 }
47 int main()
48 {
49     freopen("graph.txt","r",stdin);
50     int line,numberVertex;
51     cin >> numberVertex >> line;
52     //init c[][]
53     for(int i = 1; i <= numberVertex; i++)
54     for(int j = 1; j <= numberVertex; j++)
55         if(i != j)
56         c[i][j] = INT_MAX;
57     //c[][]对角线上为0
58     int p,q,len;
59     for(int i = 1; i <= line; i++)
60     {
61     cin >> p >> q >> len;
62     if(len < c[p][q])
63         c[p][q] = len;
64     }
65     for(int i =1; i <= numberVertex; i++)
66     {
67     for(int j = 1; j <= numberVertex; j++)
68         cout << c[i][j] << " ";
69     cout << endl;
70     }
71     //init dist[]
72     for(int i = 1; i <= numberVertex; i++)
73     dist[i] = INT_MAX;
74     dijkstra(1,numberVertex,dist,prev,c);
75     cout << dist[numberVertex] << endl;
76     return 0;
77 }