簡單題。很早以前做的。貼一下凌亂的代碼。
#include <cstdio>
#include <cstring>
int n,i,j,k,tmp,best,nbest,t1,t2;
int a[110][110],num[110];
bool flag;
int main() 
{
while (scanf("%d",&n),n) {
memset(a,0x7f,sizeof(a));
for (i=1;i<=n;i++) {
scanf("%d",&num[i]);
for (j=1;j<=num[i];j++) {
scanf("%d%d",&t1,&t2);
a[i][t1]=t2;
}
}
for (i=1;i<=n;i++) a[i][i]=0;
for (k=1;k<=n;k++)
for (i=1;i<=n;i++)
for (j=1;j<=n;j++)
if (a[i][k]!=0x7f7f7f7f && a[k][j]!=0x7f7f7f7f) a[i][j]<?=a[i][k]+a[k][j];
for (best=0x7fffffff,i=1;i<=n;i++) {
flag=false;
for (tmp=0,j=1;j<=n;j++) {
tmp>?=a[i][j];
if (a[i][j]==0x7f7f7f7f) {
flag=true;
break;
}
}
if (!flag) {
if (tmp<best) {
best=tmp;
nbest=i;
}
}
}
if (best==0x7fffffff) printf("disjoint\n");
else printf("%d %d\n",nbest,best);
}
return 0;
}