学步园

floyd

#include<stdio.h>
#include<string.h>
#define MAX 0xffffff
int map[1005][1005];
int inc[1005];
int path[1005][1005];
int main()
{
	int n;
	while(scanf("%d",&n),n){
		int i,j;
		for(i=0;i<n;i++){
			for(j=0;j<n;j++){
				scanf("%d",&map[i][j]);
				if(map[i][j]==-1)
					map[i][j]=MAX;
			}
		}
		for(i=0;i<n;i++){
			for(j=0;j<n;j++){
				path[i][j]=j;
			}
		}
		for(i=0;i<n;i++)
			scanf("%d",&inc[i]);
		int k;
		for(k=0;k<n;k++){
			for(i=0;i<n;i++){
				for(j=0;j<n;j++){
					int t=map[i][k]+map[k][j]+inc[k];
					if(t<map[i][j]){
						map[i][j]=t;
						path[i][j]=path[i][k];
					}	
					else if(t==map[i][j]){
						if(path[i][j]>path[i][k])
							path[i][j]=path[i][k];
					}
				}
			}
		}
		int begin,end;
		while(scanf("%d%d",&begin,&end),!(begin==-1&&end==-1)){
			printf("From %d to %d :\n",begin,end);
			printf("Path: ");
			begin--;
			end--;
			printf("%d",begin+1);
			for(i=begin;i!=end;i=path[i][end]){
				printf("-->%d",path[i][end]+1);
			}
			puts("");
			printf("Total cost : %d\n\n",map[begin][end]);
			//printf("-->%d\n",end+1);
		}
	}
	return 0;
}