此实现利用两个数组first[],  ext[] 邻接表。

核心代码：

void bellman_ford(int orig)
	{
		int k;
		que[tail++] = orig;
		book[orig] = 1;
		while(head < tail){
			k = first[que[head]];
			while(k != -1){
				if(dist[edge[k].v] > dist[edge[k].u] + edge[k].w){
					dist[edge[k].v] = dist[edge[k].u] + edge[k].w;
					
				if(book[edge[k].v] == 0){
					que[tail++] = edge[k].v;
					book[edge[k].v] = 1;
					}
					
				}
				k = next[k];
			}
			book[que[head]] = 0;
			head++;
		}
	}

完整实现:

#include<stdio.h>
#define INF 65535
#define MAX 20
typedef struct Edge{
	int u, v;
	int w;
}Edge;
int que[MAX] = {0};
int head = 1, tail = 1;
int next[MAX+1], first[MAX+1];
int book[MAX];
int dist[MAX];
Edge edge[MAX];

void bellman_ford(int orig)
	{
		int k;
		que[tail++] = orig;
		book[orig] = 1;
		while(head < tail){//队列不空 就继续
			k = first[que[head]];//获取 当前顶点的 ’边‘ 的 序号
			while(k != -1){
				if(dist[edge[k].v] > dist[edge[k].u] + edge[k].w){
					dist[edge[k].v] = dist[edge[k].u] + edge[k].w;
					
				if(book[edge[k].v] == 0){
					que[tail++] = edge[k].v;
					book[edge[k].v] = 1;//入队后 标记
					}
					
				}
				k = next[k];
			}
			book[que[head]] = 0;// 出队 重新把标记置 0 意味着 可以重新 入队
			head++;
		}
	}

int main()
	{
		int n, m;
		scanf("%d%d",&n,&m);
		for(int i = 1; i <= n; i++ ){//初始化
			book[i] = 0;
			first[i] = -1;
			next[i] = -1;
			dist[i] = INF;
		}	
		int orig = 1;
		dist[orig] = 0;
		for(int j = 1; j <= m; j++ ){
			scanf("%d%d%d", &edge[j].u,&edge[j].v, &edge[j].w);
			//下面两句用数组模拟链表 
			next[j] = first[edge[j].u];
			first[edge[j].u] = j;
		}

		bellman_ford(orig);
		
		for(int i = 1; i <= n; i++ ){
			printf("%d ",dist[i]);
		}
	} 
	

模拟数组的方法讲解