xtu summer individual 6 E - Find Metal Mineral
Find
2023-09-11 14:15:29 时间
Find Metal Mineral
Time Limit: 1000ms
Memory Limit: 65768KB
This problem will be judged on HDU. Original ID: 400364-bit integer IO format: %I64d Java class name: Main
Humans have discovered a kind of new metal mineral on Mars which are distributed in point‐like with paths connecting each of them which formed a tree. Now Humans launches k robots on Mars to collect them, and due to the unknown reasons, the landing site S of all robots is identified in advanced, in other word, all robot should start their job at point S. Each robot can return to Earth anywhere, and of course they cannot go back to Mars. We have research the information of all paths on Mars, including its two endpoints x, y and energy cost w. To reduce the total energy cost, we should make a optimal plan which cost minimal energy cost.
Input
There are multiple cases in the input.
In each case:
The first line specifies three integers N, S, K specifying the numbers of metal mineral, landing site and the number of robots.
The next n‐1 lines will give three integers x, y, w in each line specifying there is a path connected point x and y which should cost w.
1<=N<=10000, 1<=S<=N, 1<=k<=10, 1<=x, y<=N, 1<=w<=10000.
In each case:
The first line specifies three integers N, S, K specifying the numbers of metal mineral, landing site and the number of robots.
The next n‐1 lines will give three integers x, y, w in each line specifying there is a path connected point x and y which should cost w.
1<=N<=10000, 1<=S<=N, 1<=k<=10, 1<=x, y<=N, 1<=w<=10000.
Output
For each cases output one line with the minimal energy cost.
Sample Input
3 1 1 1 2 1 1 3 1 3 1 2 1 2 1 1 3 1
Sample Output
3 2
Hint
In the first case: 1->2->1->3 the cost is 3; In the second case: 1->2; 1->3 the cost is 2;Source
解题:传说中的树形dp。。。嗯 待会再讲吧。。。。
1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 #include <cmath> 5 #include <algorithm> 6 #include <climits> 7 #include <vector> 8 #include <queue> 9 #include <cstdlib> 10 #include <string> 11 #include <set> 12 #include <stack> 13 #define LL long long 14 #define INF 0x3f3f3f3f 15 using namespace std; 16 struct arc { 17 int to,w; 18 }; 19 vector<arc>g[10010]; 20 int dp[10010][15],n,s,k; 21 void dfs(int u,int fa){ 22 for(int i = 0; i < g[u].size(); i++){ 23 int v = g[u][i].to; 24 if(v == fa) continue; 25 dfs(v,u); 26 for(int t = k; t >= 0; t--){ 27 dp[u][t] += dp[v][0] + 2*g[u][i].w; 28 for(int j = 1; j <= t; j++) 29 dp[u][t] = min(dp[u][t],dp[u][t-j]+dp[v][j]+j*g[u][i].w); 30 } 31 } 32 } 33 int main(){ 34 while(~scanf("%d%d%d",&n,&s,&k)){ 35 for(int i = 0; i <= n; i++) 36 g[i].clear(); 37 for(int i = 1; i < n; i++){ 38 int u,v,w; 39 scanf("%d %d %d",&u,&v,&w); 40 g[u].push_back((arc){v,w}); 41 g[v].push_back((arc){u,w}); 42 } 43 memset(dp,0,sizeof(dp)); 44 dfs(s,-1); 45 printf("%d\n",dp[s][k]); 46 } 47 return 0; 48 }
相关文章
- 【解决】Maven myeclipse出现Could not find the main class
- find命令find -name 文件名
- 解决php configure: error: Cannot find ldap libraries in /usr/lib.错误
- Array对象的方法实现(3)----Array.prototype.filter和Array.prototype.find(实现常规参数的功能)
- Linux find命令之exec
- cordova蓝牙插件 npm ERR! enoent This is related to npm not being able to find a file.
- 解决:Could not find debuginfo pkg for dependency package glibc-2.12-1.132.el6_5.3.i686
- 问题解决了,可是为什么呢?could not find the main class.program will exitmain
- 成功解决OSError: [E050] Can‘t find model ‘en_core_web_sm‘. It doesn‘t seem to be a Python package or a v
- 成功解决raise Py4JError py4j.protocol.Py4JError: py4j.protocol.Py4JError: Could not find py4j jar at
- 成功解决ImportError: Could not find 'msvcp140.dll'. TensorFlow requires that this DLL be installed in a
- 【异常】Maven构建报错 repackage failed: Unable to find a single main class from the following candidates
- 30个在开发中常用的linux命令以及linux常用快捷键,比如pwd,which,ls,cd,cat,tail,touch,mkdir,cp,mv,sudo,chown,find,yum,ps等
- 再说linux中的rm mv 遍历执行多个文件的操作: find + xagrs
- Android的java的报错提示:Could not find com.android.tools.build:gradle:4.2.2.
- find命令常用