To_Heart—题解——CF301B
思路:最短路
每两个点的距离为
(
∣
x
1
−
x
2
∣
+
∣
y
1
−
y
2
∣
)
∗
d
−
a
[
j
]
(|x_1-x_2|+|y_1-y_2|)*d-a[j]
(∣x1−x2∣+∣y1−y2∣)∗d−a[j],其中j为走到第j个点的可恢复的单位时间的大小
然后跑一遍dijkstra即可
#include<bits/stdc++.h>
#include<queue>
#include<vector>
using namespace std;
struct zz{
int v;
int w;
bool operator < (const zz x) const
{ return x.w<w; }
};
vector<zz> v[2505];
int n,d,INF;
int dp[2505];
int a[100005];
int x[100005];
int y[100005];
bool f[2505];
void Dijkstra(int s,int t){
dp[s]=0;
priority_queue<zz> q;
zz Now;
Now.v=s;
Now.w=dp[s];
q.push(Now);
while(q.size()){
zz now=q.top();
q.pop();
if(f[now.v]){
continue;
}
f[now.v]=1;
int k=now.v;
for(int j=0;j<v[k].size();j++){
if(dp[k]+v[k][j].w<dp[v[k][j].v]){
dp[v[k][j].v]=dp[k]+v[k][j].w;
zz NOW;
NOW.w=dp[v[k][j].v];
NOW.v=v[k][j].v;
q.push(NOW);
}
}
}
printf("%d\n",dp[t]);
}
int main(){
memset(dp,0x3f,sizeof dp);
scanf("%d%d",&n,&d);
for(int i=2;i<n;i++) scanf("%d",&a[i]);
for(int i=1;i<=n;i++) scanf("%d%d",&x[i],&y[i]);
for(int i=1;i<=n;i++){
for(int j=i+1;j<=n;j++){
int dist=(abs(x[j]-x[i])+abs(y[j]-y[i]))*d;
v[i].push_back(zz{j,dist-a[j]});
v[j].push_back(zz{i,dist-a[i]});
}
}
//cin>>s>>t;
Dijkstra(1,n);
return 0;
}