hdu6090 菊花图
Posted Billyshuai
tags:
篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了hdu6090 菊花图相关的知识,希望对你有一定的参考价值。
Rikka with Graph
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)
Total Submission(s): 239 Accepted Submission(s): 157
Problem Description
As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is one of them:
For an undirected graph G with n nodes and m edges, we can define the distance between (i,j) (dist(i,j) ) as the length of the shortest path between i and j . The length of a path is equal to the number of the edges on it. Specially, if there are no path between i and j , we make dist(i,j) equal to n .
Then, we can define the weight of the graph G (wG ) as ∑ni=1∑nj=1dist(i,j) .
Now, Yuta has n nodes, and he wants to choose no more than m pairs of nodes (i,j)(i≠j) and then link edges between each pair. In this way, he can get an undirected graph G with n nodes and no more than m edges.
Yuta wants to know the minimal value of wG .
It is too difficult for Rikka. Can you help her?
In the sample, Yuta can choose (1,2),(1,4),(2,4),(2,3),(3,4) .
For an undirected graph G with n nodes and m edges, we can define the distance between (i,j) (dist(i,j) ) as the length of the shortest path between i and j . The length of a path is equal to the number of the edges on it. Specially, if there are no path between i and j , we make dist(i,j) equal to n .
Then, we can define the weight of the graph G (wG ) as ∑ni=1∑nj=1dist(i,j) .
Now, Yuta has n nodes, and he wants to choose no more than m pairs of nodes (i,j)(i≠j) and then link edges between each pair. In this way, he can get an undirected graph G with n nodes and no more than m edges.
Yuta wants to know the minimal value of wG .
It is too difficult for Rikka. Can you help her?
In the sample, Yuta can choose (1,2),(1,4),(2,4),(2,3),(3,4) .
Input
The first line contains a number t(1≤t≤10)
, the number of the testcases.
For each testcase, the first line contains two numbers n,m(1≤n≤106,1≤m≤1012) .
For each testcase, the first line contains two numbers n,m(1≤n≤106,1≤m≤1012) .
Output
For each testcase, print a single line with a single number -- the answer.
Sample Input
1
4 5
Sample Output
14
#include<cstdio> #include<cstring> #include<algorithm> using namespace std; int main() { int T; for(scanf("%d",&T); T--;) { long long n,m; scanf("%I64d%I64d",&n,&m); long long maxx=n*(n-1)/2; if(m>=maxx) printf("%I64d\\n",maxx*2); else if(m>=n-1) printf("%I64d\\n",2*(n-1)*(n-1)-2*(m-n+1)); else printf("%I64d\\n",2*m*m+(n-m-1)*(m+1)*n*2+(n-m-1)*(n-m-2)*n); } }
以上是关于hdu6090 菊花图的主要内容,如果未能解决你的问题,请参考以下文章
HDU 6090 17多校5 Rikka with Graph(思维简单题)
HDU 6090 Rikka with Graph —— 2017 Multi-University Training 5