結果
問題 | No.2214 Products on Tree |
ユーザー |
👑 |
提出日時 | 2023-02-10 21:24:21 |
言語 | D (dmd 2.109.1) |
結果 |
AC
|
実行時間 | 202 ms / 3,000 ms |
コード長 | 3,898 bytes |
コンパイル時間 | 1,684 ms |
コンパイル使用メモリ | 151,900 KB |
実行使用メモリ | 43,776 KB |
最終ジャッジ日時 | 2024-06-22 17:27:18 |
合計ジャッジ時間 | 8,274 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge2 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 35 |
ソースコード
import std.conv, std.functional, std.range, std.stdio, std.string;import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;import core.bitop;class EOFException : Throwable { this() { super("EOF"); } }string[] tokens;string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }int readInt() { return readToken.to!int; }long readLong() { return readToken.to!long; }bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1;(unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }struct ModInt(uint M_) {import std.conv : to;alias M = M_;uint x;this(ModInt a) { x = a.x; }this(uint x_) { x = x_ % M; }this(ulong x_) { x = cast(uint)(x_ % M); }this(int x_) { x = ((x_ %= cast(int)(M)) < 0) ? (x_ + cast(int)(M)) : x_; }this(long x_) { x = cast(uint)(((x_ %= cast(long)(M)) < 0) ? (x_ + cast(long)(M)) : x_); }ref ModInt opAssign(T)(inout(T) a) if (is(T == uint) || is(T == ulong) || is(T == int) || is(T == long)) { return this = ModInt(a); }ref ModInt opOpAssign(string op, T)(T a) {static if (is(T == ModInt)) {static if (op == "+") { x = ((x += a.x) >= M) ? (x - M) : x; }else static if (op == "-") { x = ((x -= a.x) >= M) ? (x + M) : x; }else static if (op == "*") { x = cast(uint)((cast(ulong)(x) * a.x) % M); }else static if (op == "/") { this *= a.inv(); }else static assert(false);return this;} else static if (op == "^^") {if (a < 0) return this = inv()^^(-a);ModInt b = this, c = 1U;for (long e = a; e; e >>= 1) { if (e & 1) c *= b; b *= b; }return this = c;} else {return mixin("this " ~ op ~ "= ModInt(a)");}}ModInt inv() const {uint a = M, b = x; int y = 0, z = 1;for (; b; ) { const q = a / b; const c = a - q * b; a = b; b = c; const w = y - cast(int)(q) * z; y = z; z = w; }assert(a == 1); return ModInt(y);}ModInt opUnary(string op)() const {static if (op == "+") { return this; }else static if (op == "-") { ModInt a; a.x = x ? (M - x) : 0U; return a; }else static assert(false);}ModInt opBinary(string op, T)(T a) const { return mixin("ModInt(this) " ~ op ~ "= a"); }ModInt opBinaryRight(string op, T)(T a) const { return mixin("ModInt(a) " ~ op ~ "= this"); }bool opCast(T: bool)() const { return (x != 0U); }string toString() const { return x.to!string; }}enum MO = 998244353;alias Mint = ModInt!MO;int N;int[] A, B;int[][] graph;Mint[2][] dp;void dfs(int u, int p) {Mint f0 = 1, f1 = 1;foreach (v; graph[u]) if (p != v) {dfs(v, u);Mint g0, g1;// cutg0 += f0 * dp[v][1];g1 += f1 * dp[v][1];// conng0 += f0 * dp[v][0];g1 += f0 * dp[v][1];g1 += f1 * dp[v][0];f0 = g0;f1 = g1;}dp[u][0] = f0;dp[u][1] = f1;}void main() {try {for (; ; ) {N = readInt;A = new int[N - 1];B = new int[N - 1];foreach (i; 0 .. N - 1) {A[i] = readInt - 1;B[i] = readInt - 1;}graph = new int[][N];foreach (i; 0 .. N - 1) {graph[A[i]] ~= B[i];graph[B[i]] ~= A[i];}dp = new Mint[2][N];dfs(0, -1);writeln(dp[0][1]);}} catch (EOFException e) {}}