OJ-Problems-Source/HDOJ/1874_autoAC.cpp
2016-08-17 15:13:51 +08:00

37 lines
1008 B
C++

#include <stdio.h>
#include <string.h>
#include <algorithm>
using namespace std;
const int M=2005;
#define min(a,b) a<b?a:b
int map[M][M];
#define inf 0xffffff
int main()
{
int n,m,i,j,k,s,e,l,s1,e1;
while(scanf("%d%d",&n,&m)!=EOF)
{
for(i=0;i<n;i++)
for(j=0;j<n;j++)
map[i][j]=inf;
for(i=0;i<m;i++)
{
scanf("%d%d%d",&s,&e,&l);
if(map[s][e]>l)
map[s][e]=map[e][s]=l;
}
for(k=0;k<n;k++)
for(i=0;i<n;i++)
for(j=0;j<n;j++)
map[i][j]=min(map[i][j],map[i][k]+map[k][j]);
scanf("%d%d",&s1,&e1);
if(s1==e1)
printf("0\n");
else if(map[s1][e1]==inf)
printf("-1\n");
else
printf("%d\n",map[s1][e1]);
}
return 0;
}