結果
| 問題 |
No.977 アリス仕掛けの摩天楼
|
| ユーザー |
 Oland
|
| 提出日時 | 2020-02-01 09:27:32 |
| 言語 | Java (openjdk 23) |
| 結果 |
AC
|
| 実行時間 | 198 ms / 2,000 ms |
| コード長 | 8,346 bytes |
| コンパイル時間 | 2,316 ms |
| コンパイル使用メモリ | 78,816 KB |
| 実行使用メモリ | 55,708 KB |
| 最終ジャッジ日時 | 2024-09-18 19:45:12 |
| 合計ジャッジ時間 | 5,829 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge1 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| other | AC * 26 |
ソースコード
import java.util.*;
import java.io.*;
@SuppressWarnings("unused")
public class Main {
FastScanner in;
PrintWriter out;
int MOD = (int)1e9+7;
long ceil(long a, long b){return (a + b - 1) / b;}
long gcd(long a, long b){return b == 0 ? a : gcd(b, a % b);}
long lcm(long a, long b){return a / gcd(a, b) * b;}
void solve(){
int N = in.nextInt();
UnionFind uf = new UnionFind(N);
int[] deg = new int[N];
for(int i = 0; i < N - 1; i++){
int a = in.nextInt(), b = in.nextInt();
uf.union(a, b);
deg[a]++;
deg[b]++;
}
int[] numDeg = new int[N+1];
for(int i = 0; i < N; i++) numDeg[deg[i]]++;
out.println(uf.group > 2 || (uf.group == 2 && !(numDeg[0] == 1 && numDeg[2] == N-1)) ? "Alice" : "Bob");
}
class UnionFind{
private int[] par;
private int[] rank;
private int[] size;
int group;
UnionFind(int n){
par = new int[n];
rank = new int[n];
size = new int[n];
group = n;
for(int i = 0; i < n; i++){
par[i] = i;
rank[i] = 0;
size[i] = 1;
}
}
//ランクの小さいほうにつなげる
boolean union(int x, int y){
x = find(x);
y = find(y);
if(x == y) return false;
if(rank[x] < rank[y]){
int tmp = x; x = y; y = tmp;
}
//y(のroot)をx(のroot)の下にくっつける
//yのほうが重くなる(ポテンシャルが高くなる)
if(rank[x] == rank[y]) rank[x]++;
group--;
par[y] = x;
size[x] += size[y];
return true;
}
//経路圧縮しながらrootを求める
int find(int x){
if(par[x] == x){
return x;
}else{
int f = find(par[x]);
return par[x] = f;
}
}
int rank(int x){return rank[find(x)];}
int size(int x){return size[find(x)];}
boolean isSame(int x, int y){
return find(x) == find(y);
}
}
public static void main(String[] args) {
new Main().m();
}
private void m() {
in = new FastScanner(System.in);
out = new PrintWriter(System.out);
/*
try {
String path = "input.txt";
out = new PrintWriter(new BufferedWriter(new FileWriter(new File(path))));
}catch (IOException e){
e.printStackTrace();
}
*/
solve();
out.flush();
in.close();
out.close();
}
static class FastScanner {
private Reader input;
public FastScanner() {this(System.in);}
public FastScanner(InputStream stream) {this.input = new BufferedReader(new InputStreamReader(stream));}
public void close() {
try {
this.input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public int nextInt() {return (int) nextLong();}
public long nextLong() {
try {
int sign = 1;
int b = input.read();
while ((b < '0' || '9' < b) && b != '-' && b != '+') {
b = input.read();
}
if (b == '-') {
sign = -1;
b = input.read();
} else if (b == '+') {
b = input.read();
}
long ret = b - '0';
while (true) {
b = input.read();
if (b < '0' || '9' < b) return ret * sign;
ret *= 10;
ret += b - '0';
}
} catch (IOException e) {
e.printStackTrace();
return -1;
}
}
public double nextDouble() {
try {
double sign = 1;
int b = input.read();
while ((b < '0' || '9' < b) && b != '-' && b != '+') {
b = input.read();
}
if (b == '-') {
sign = -1;
b = input.read();
} else if (b == '+') {
b = input.read();
}
double ret = b - '0';
while (true) {
b = input.read();
if (b < '0' || '9' < b) break;
ret *= 10;
ret += b - '0';
}
if (b != '.') return sign * ret;
double div = 1;
b = input.read();
while ('0' <= b && b <= '9') {
ret *= 10;
ret += b - '0';
div *= 10;
b = input.read();
}
return sign * ret / div;
} catch (IOException e) {
e.printStackTrace();
return Double.NaN;
}
}
public char nextChar() {
try {
int b = input.read();
while (Character.isWhitespace(b)) {
b = input.read();
}
return (char) b;
} catch (IOException e) {
e.printStackTrace();
return 0;
}
}
public String nextStr() {
try {
StringBuilder sb = new StringBuilder();
int b = input.read();
while (Character.isWhitespace(b)) {
b = input.read();
}
while (b != -1 && !Character.isWhitespace(b)) {
sb.append((char) b);
b = input.read();
}
return sb.toString();
} catch (IOException e) {
e.printStackTrace();
return "";
}
}
public String nextLine() {
try {
StringBuilder sb = new StringBuilder();
int b = input.read();
while (b != -1 && b != '\n') {
sb.append((char) b);
b = input.read();
}
return sb.toString();
} catch (IOException e) {
e.printStackTrace();
return "";
}
}
public int[] nextIntArray(int n) {
int[] res = new int[n];
for (int i = 0; i < n; i++) {
res[i] = nextInt();
}
return res;
}
public int[] nextIntArrayDec(int n) {
int[] res = new int[n];
for (int i = 0; i < n; i++) {
res[i] = nextInt() - 1;
}
return res;
}
public int[] nextIntArray1Index(int n) {
int[] res = new int[n + 1];
for (int i = 0; i < n; i++) {
res[i + 1] = nextInt();
}
return res;
}
public long[] nextLongArray(int n) {
long[] res = new long[n];
for (int i = 0; i < n; i++) {
res[i] = nextLong();
}
return res;
}
public long[] nextLongArrayDec(int n) {
long[] res = new long[n];
for (int i = 0; i < n; i++) {
res[i] = nextLong() - 1;
}
return res;
}
public long[] nextLongArray1Index(int n) {
long[] res = new long[n + 1];
for (int i = 0; i < n; i++) {
res[i + 1] = nextLong();
}
return res;
}
public double[] nextDoubleArray(int n) {
double[] res = new double[n];
for (int i = 0; i < n; i++) {
res[i] = nextDouble();
}
return res;
}
}
}