hdu1874(畅通工程续)

http://acm.hdu.edu.cn/showproblem.php?pid=1874

View Code

#include < iostream >
#define _max 9999999
#define M 201
using namespace std;
int map[M][M];
int visit[M];
int dir[M];
int n , m ;
int a , b , c ;
int len;
void Init( int n)
{
int i,j;
for (i = 0 ; i < n ; i ++ )
{
for (j = 0 ; j < n; j ++ )
map[i][j] = _max;
}
}
void DJ( int v)
{
int i,j,p,k ,_min;
for (i = 0 ;i <= n;i ++ )
dir[i] = map[v][i];
dir[v] = 0 ;
visit[v] = true ;
for (i = 0 ;i <= n;i ++ )
{
_min = _max;
for (j = 0 ;j < n;j ++ )
{
if ( ! visit[j] && _min > dir[j])
{
_min = dir[j];
k = j;
}
}
visit[k] = true ;
for ( p = 0 ; p < n; p ++ )
{
if ( ! visit[p] && dir[p] > dir[k] + map[k][p])
{
dir[p] = dir[k] + map[k][p];
}
}
}
}
int main()
{

while (cin >> n >> m)
{
Init(n);
int i;
int s,e;
for (i = 0 ;i < m;i ++ )
{
cin >> a >> b >> c;
if (map[a][b] > c) map[a][b] = map[b][a] = c;

}
memset(visit , false , sizeof (visit));
cin >> s >> e;
DJ(s);
if (dir[e] < _max)cout << dir[e] << endl;
else cout << " -1 " << endl;
}
return 0 ;

}

转载于:https://www.cnblogs.com/FCWORLD/archive/2011/05/20/2052338.html