HDOJ 2544 BellmanFord实现

 1 #include <cstdio>
 2 
 3 struct road{
 4     int head;
 5     int tail;
 6     int value;
 7 };
 8 
 9 #define Infinity 233333333
10 
11 int main(){
12     int n, m;
13     while (scanf("%d %d", &n, &m), n != 0){
14         road roads[m];
15         int dis[n];
16         for (int i = 0; i < m; i++)
17             scanf("%d %d %d", &roads[i].head, &roads[i].tail, &roads[i].value);
18         dis[0] = 0;
19         for (int i = 1; i < n; i++)
20             dis[i] = Infinity;
21         for (int i = 0; i < n - 1; i++)
22             for (int j = 0; j < m; j++){
23                 int head, tail;
24                 if (dis[roads[j].tail - 1] > dis[roads[j].head - 1]){
25                     head = roads[j].head - 1;
26                     tail = roads[j].tail - 1;
27                 }
28                 else{
29                     head = roads[j].tail - 1;
30                     tail = roads[j].head - 1;
31                 }
32                 if (dis[tail] > dis[head] + roads[j].value)
33                     dis[tail] = dis[head] + roads[j].value;
34             }
35         printf("%d
", dis[n - 1]);
36     }
37     return 0;
38 }