hdu 1874 畅通工程续（bellman-ford，dijkstra）

bellman-ford：

#include <stdio.h>
#define INF 99999999
int u[2200],v[2200],w[2200];
int dis[210];
int main()
{
int n,m,i,k;
while(scanf("%d %d",&n,&m) != EOF)
{
for(i = 0; i < m; ++i)
{
scanf("%d %d %d",&u[i],&v[i],&w[i]);
u[i+m] = v[i];
v[i+m] = u[i];
w[i+m] = w[i];
}
int start,end;
scanf("%d %d",&start,&end);
for(i = 0; i < n; ++i)
dis[i] = INF;
dis[start] = 0;
for(k = 0; k < n; ++k)
for(i = 0; i < 2*m; ++i)
if(dis[v[i]] > dis[u[i]] + w[i])
dis[v[i]] = dis[u[i]] + w[i];
if(dis[end] < INF)
printf("%d\n",dis[end]);
else
printf("-1\n");
}
return 0;
}

#include <iostream>
#include <cstring>
using namespace std;
#define INF 99999999
int map[200][200];
int dis[200];
int book[200];
int n,m;
int main()
{
int S,T,i,k,j,x,y,z;
while(cin >> n >> m)
{
for(i = 0; i < n; ++i)
for(j = 0; j < n; ++j)
if(i == j) map[i][j] = 0;
else map[i][j] = INF;

for(i = 0; i < m; ++i)
{
cin >> x >> y >> z;
if(z < map[x][y])
map[x][y] = map[y][x] = z;
}
memset(book,0,sizeof(book));
cin >> S >> T;
for(i = 0; i < n; ++i)
dis[i] = map[S][i];
book[S] = 1;
int min = INF;
int u,v;
for(k = 0; k < n; ++k)
{
min = INF;
for(i = 0; i < n; ++i)
if(!book[i] && min > dis[i]){ min = dis[i]; u = i;}
book[u] = 1;
for(v = 0; v < n; ++v)
dis[v] = dis[v] < dis[u]+map[u][v] ? dis[v]:dis[u]+map[u][v];
}
if(dis[T] != INF)
cout << dis[T] << endl;
else
cout << "-1" << endl;
}
return 0;
}