Codeforces 212E IT Restaurants tree dp (water

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Test instructions

Given n points of the tree, dyed two colors, different colors can not be adjacent and to be as many nodes to dye. Find the number of possible staining nodes for color A and color B. (Copy from Figo)

And at least one dianran a, at least one Dianran b

Dp[i][j]=1 indicates that I Dianran j a color is feasible =0 expression is not feasible.

Import Java.io.bufferedreader;import Java.io.inputstreamreader;import Java.io.printwriter;import Java.math.biginteger;import Java.text.decimalformat;import Java.util.arraydeque;import Java.util.ArrayList;import Java.util.arrays;import Java.util.collection;import Java.util.collections;import Java.util.Comparator;import Java.util.deque;import Java.util.hashmap;import Java.util.iterator;import Java.util.linkedlist;import Java.util.map;import Java.util.priorityqueue;import Java.util.scanner;import Java.util.stack;import Java.util.stringtokenizer;import Java.util.treemap;import Java.util.treeset;import Java.util.Queue;import Java.io.file;import Java.io.fileinputstream;import Java.io.filenotfoundexception;import Java.io.FileOutputStream; public class Main {arraylist<integer> L = new ArrayList (), R = new ArrayList (); int[][] dp = new int[n][n];//A subtree representing the I point Can get up to a few blue int[when dyeing j red] Siz = new Int[n], ans = new int[n];int n;void dfs (int u, int fa) {for (int i = 2; I <= N; i++) dp[u][ I] = 0;dp[u][0] = 1;siz[u] = 1;for (int i = head[u]; i!=-1; i = edge[i].nex) {int v = edge[i].to; if (v = = FA) Continue;dfs (V, u); Siz[u] + = s iz[v];for (int j = n-1; J >= 0; j--) if (dp[u][j]>0) dp[u][j+siz[v]] = 1;} int s = n-siz[u];for (int i = n-1; I >= 0; i--) if (dp[u][i]>0) dp[u][i+s] = 1;for (int i = 1; i < n-1; i++) if (dp[u][i ]>0) Ans[i] = 1;}  void work () throws Exception {Init_edge (); n = int (); for (int i = 0; I <= N; i++) ans[i] = 0;for (Int i = 1, u, v; i< N; i++) {u =int (); v = Int (); Add (u,v,1); add (v,u,1);} DFS (1,-1); int len = 0;for (int i = 1; i < n-1; i++) len + ans[i];out.println (len), for (int i = 1; i < n-1; i++) if (ans[ i]>0) {out.println (i+ "" + (N-1-i))}} public static void Main (string[] args) throws Exception {main wo = new main (), in = new BufferedReader (New Inputstreamreade R (system.in)); out = new PrintWriter (system.out);//in = new BufferedReader (New InputStreamReader ( new//file ("Input.txt"))),//out = new PrintWriter (New File ("Output.txt")), Wo.work (); out.Close ();} static int N = 5050;static int M = N * 2;decimalformat df = new DecimalFormat ("0.0000"); static int inf = (int) 1e9;static  Long inf64 = (long) 1e18;static double EPS = 1e-8;static double Pi = math.pi;static int mod = (int) 1e9 + 7;private String Next () throws Exception {while (str = = NULL | |!str.hasmoreelements ()) str = new StringTokenizer (In.readline ()); return str . NextToken ();} private int int () throws Exception {return Integer.parseint (Next ());} Private long Long () throws Exception {return Long.parselong (Next ());} Private double double () throws Exception {return double.parsedouble (Next ());} StringTokenizer str;static Scanner cin = new Scanner (system.in); static BufferedReader in;static printwriter out;class EDG E{int from, to, DIS, NEX; Edge () {} edge (int from, int to, int. dis, int nex) {this.from = from; this.to = to; this.dis = dis; This.nex =nex;}} Edge[] Edge = new edge[m<<1]; Int[] head = new Int[n]; int edgenum; void Init_edge () {for (int i = 0; i < N; i++) head[i] = 1; Edgenum = 0;} void Add (int u, int v, int dis) {Edge[edgenum] = new Edge (u, V, dis, head[u]); Head[u] = edgenum++;}/* */int Upper_bound (int[] A, int l, int r, int val) {//Upper_bound (a+l,a+r,val)-a;int pos = R;r--;while (l <= r) {int mid = (L + R) >> 1;if (A[mid] <= val) {L = Mid + 1;} else {pos = Mid;r = Mid-1;}} return POS;} int Lower_bound (int[] A, int l, int r, int val) {//Upper_bound (a+l,a+r,val)-a;int pos = R;r--;while (l <= r) {int mid = (L + R) >> 1;if (A[mid] < val) {L = mid + 1;} else {pos = Mid;r = Mid-1;}} return POS;} int Pow (int x, int y) {int ans = 1;while (Y > 0) {if ((Y & 1) > 0) ans *= x;y >>= 1;x = x * x;} return ans;} Double Pow (double x, int y) {double ans = 1;while (Y > 0) {if ((Y & 1) > 0) ans *= x;y >>= 1;x = x * x;} return ans;} int pow_mod (int x, int y, int Mod) {int ans = 1;while (Y > 0) {if ((Y & 1) > 0) ans *= x;ans%= mod;y >>= 1 ; x = x * x;x%= mod;} return ans;} Long Pow (long x, long y) {LOng ans = 1;while (Y > 0) {if ((Y & 1) > 0) ans *= x;y >>= 1;x = x * x;} return ans;} Long Pow_mod (long x, long y, long Mod) {Long ans = 1;while (Y > 0) {if ((Y & 1) > 0) ans *= x;ans%= mod;y &GT;&G t;= 1;x = x * x;x%= mod;} return ans;} int gcd (int x, int y) {if (x > y) {int tmp = X;X = Y;y = tmp;} while (x > 0) {y%= x;int tmp = x;x = Y;y = tmp;} return y;} int max (int x, int y) {return x > y x:y;} int min (int x, int y) {return x < y x:y;} Double Max (double x, double y) {return x > y x:y;} Double min (double x, double y) {return x < y x:y;} Long Max (long x, long y) {return x > y x:y;} Long min (long x, long y) {return x < y x:y;} int abs (int x) {return x > 0 ×:-X;} Double abs (double x) {return x > 0 ×:-X;} Long ABS (long x) {return x > 0 ×:-X;} Boolean zero (double x) {return abs (x) < EPS;} Double sin (double x) {return Math.sin (x);} Double cos (double x) {return math.cos (x);} Double tan (double x) {return math.tan (x);} Double sqrt (double x) {return math.sqrt (x);}}

Codeforces 212E IT Restaurants tree dp (water