Poj 1655 balancing act tree center of gravity

Question: Here is a tree that asks you for the center of gravity. The new definition of the tree is that if you remove this node, the maximum number of subtree nodes of this node is the minimum.

Solution:

Dynamic Planning, tree-like DP

It is found that the vector performance is worse than that of array pointers.

Solution code:

1 // file name: poj1741.cpp 2 // Author: darkdream 3 // created time:, Sunday, October 05, 2014, 4, 5, # include <vector> 6 # include <list> 7 # include <map> 8 # include <set> 9 # include <deque> 10 # include <stack> 11 # include <bitset> 12 # include <algorithm> 13 # include <functional> 14 # include <numeric> 15 # include <utility> 16 # include <sstream> 17 # include <iostream> 18 # include <iomanip> 19 # include <cstdio> 20 # include <cmat H> 21 # include <cstdlib> 22 # include <cstring> 23 # include <ctime> 24 # define ll long long25 # define maxn 2001026 using namespace STD; 27 int ans; 28 int ansv; 29 int MX [maxn]; 30 int sum [maxn]; 31 int visit [maxn]; 32 vector <int> MP [maxn]; 33 void DFS (int K) 34 {35 // printf ("% d \ n", k); 36 int num = MP [K]. size (); 37 sum [k] = 1; 38 for (INT I = 0; I <num; I ++) 39 {40 if (! Visit [MP [k] [I]) 41 {42 visit [MP [k] [I] = 1; 43 DFS (MP [k] [I]); 44 MX [k] = max (sum [MP [k] [I], MX [k]); 45 sum [k] + = sum [MP [k] [I]; 46} 47} 48} 49 int main () {50 int T; 51 scanf ("% d", & T); 52 while (t --) 53 {54 int N; 55 scanf ("% d", & N); 56 int U, v; 57 for (INT I = 1; I <= N; I ++) 58 MP [I]. clear (); 59 for (INT I = 1; I <n; I ++) 60 {61 scanf ("% d", & U, & V ); 62 MP [u]. push_back (V); 63 MP [v]. push_back (U); 64} 65 memset (MX, 0, sizeof (INT) * (n + 1); 66 memset (visit, 0, sizeof (INT) * (n + 1); 67 visit [1] = 1; 68 DFS (1); 69 ansv = 1e9; 70 for (INT I = 1; I <= N; I ++) 71 {72 int tmx = max (sum [1]-sum [I], MX [I]); 73 If (tmx <ansv) 74 {75 ans = I; 76 ansv = tmx; 77} 78} 79 printf ("% d \ n", ANS, ansv); 80} 81 return 0; 82}

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Poj 1655 balancing act tree center of gravity