bzoj1774. [Usaco2009 Dec]Toll 过路费 题解

#include<bits/stdc++.h>
using namespace std;
inline int read(){int res=0,f=1;char ch=getchar();while(ch<'0'ch>'9'){if(ch=='-') f=-1;ch=getchar();}while(ch>='0'&&ch<='9') res=res*10+ch-'0',ch=getchar();return res*f;}
inline void write(int x){if(x<0) putchar('-'),x=-x;if(x<10) putchar(x+'0');else write(x/10),putchar(x%10+'0');}
int n,m,q,f[255][255],ans[255][255],g[255];
struct node{int v,id;}a[255];
inline int cmp(node x,node y){return x.v<y.v;}
int main(){
n=read(),m=read(),q=read();
for(int i=1;i<=n;i++) a[i].v=read(),a[i].id=i;
memset(f,63,sizeof(f));
memset(ans,63,sizeof(ans));
for(int i=1;i<=n;i++) f[i][i]=ans[i][i]=a[i].v;
for(int x,y,z,i=1;i<=m;i++){
x=read(),y=read(),z=read();
f[x][y]=f[y][x]=min(f[x][y],z);
}
sort(a+1,a+n+1,cmp);
for(int i=1;i<=n;i++) g[a[i].id]=i;
#define mid a[k].id
#define val a[k].v
for(int k=1;k<=n;k++){
for(int i=1;i<=n;i++){
for(int j=1;j<=n;j++){
f[i][j]=min(f[i][j],f[i][mid]+f[mid][j]);
ans[i][j]=min(ans[i][j],f[i][j]+max(val,max(a[g[i]].v,a[g[j]].v)));
}
}
}
#undef mid
#undef val
for(int x,y,i=1;i<=q;i++){
x=read(),y=read();
write(ans[x][y]),putchar('\n');
}
return 0;
}