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最短路径dijkstra算法

#include<stdio.h>
#include<string.h>

#define NUM 100
#define maxint 10000

void dijkstra(int n,int v,int dist[],int prev[],int c[][NUM])
{
	int i,j;
	bool s[NUM];
	for(i=1; i<=n; i++)
	{
		dist[i] = c[v][i];
		s[i] = false;
		if (dist[i]>maxint) prev[i] = 0;
		else prev[i] = v;
	}
	dist[v] = 0;
	s[v] = true;
	for(i=1; i<n; i++)
	{
		int tmp = maxint;
		int u = v;
		for(j=1; j<=n; j++)
			if(!(s[j]) && (dist[j]<tmp))
			{
				u = j;
				tmp = dist[j];
			}
		s[u] = 1;
		for(j=1; j<=n; j++)
			if(!(s[j]) && c[u][j]<maxint)
			{
				int newdist = dist[u]+c[u][j];
				if (newdist<dist[j])
				{
					dist[j] = newdist;
					prev[j] = u;
				}
			}
	}
}

int main()
{
	int m,n;
	while(scanf("%d%d",&n,&m)!=EOF && (m || n))
	{
		int i,j;
		int dist[NUM] = {0};
		int prev[NUM] = {0};
		int c[NUM][NUM];
		memset(c,1,sizeof(c));//16843009
	//	printf("%d",c[0][0]);
		int v,w,edge;
		for(i=0; i<m; i++)
		{
			scanf("%d%d%d",&v,&w,&edge);
			c[v][w] = edge;
		}
		dijkstra(n,1,dist,prev,c);
		for(i=2; i<=n; i++)
			printf("%d ",dist[i]);
		printf("\n");
		for(j=2; j<=n; j++)
		{
			printf("%d",j);
			int t = prev[j];
			while (t!=1)
			{
				printf("-->%d",t);
				t=prev[t];
			}
			printf("-->1\n");
		}
	}
	return 0;
}
           

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