POJ 1655-balancing Act (tree dp)

Test instructions

To find out which node in the tree of n nodes is removed, the maximum connectivity component is minimized.

Analysis: The previous question

#include <map>#include<Set>#include<list>#include<cmath>#include<queue>#include<stack>#include<cstdio>#include<vector>#include<string>#include<cctype>#include<complex>#include<cassert>#include<utility>#include<cstring>#include<cstdlib>#include<iostream>#include<algorithm>using namespaceStd;typedef pair<int,int>Pii;typedefLong Longll;#defineLson l,m,rt<<1#definePi ACOs (-1.0)#defineRson m+1,r,rt<<11#defineAll 1,n,1#defineN 20010#defineRead Freopen ("In.txt", "R", stdin)Constll infll =0x3f3f3f3f3f3f3f3fll;Const intinf=0x7ffffff;Const intMoD =1000000007;intDp[n],n,num[n],used[n];vector<int>E[n];intDfsintroot) {Num[root]=1; Used[root]=1;  for(intI=0; I<e[root].size (); + +i) {        intson=E[root][i]; if(Used[son])Continue; Num[root]+=Dfs (son); Dp[root]=Max (Dp[root],num[son]); } Dp[root]=max (dp[root],n-Num[root]); returnnum[root];}intMain () {intT; scanf ("%d",&t);  while(t--) {scanf ("%d",&N); Memset (DP,0,sizeof(DP)); memset (Used,0,sizeof(used));  for(intI=1; i<=n;++i) e[i].clear (); intb;  for(intI=0; i<n-1;++i) {scanf ("%d%d",&a,&b);            E[a].push_back (b);        E[b].push_back (a); } DFS (1); inttmp=1;  for(intI=2; i<n;++i)if(dp[tmp]>Dp[i]) tmp=i; printf ("%d%d\n", tmp,dp[tmp]); }return 0;}

POJ 1655-balancing Act (tree dp)