Regionals 2011 >> Asia

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给定一个长度不超过40的数字串s，求斐波那契数列的前十万项中，最小的一个前缀为s的数的下标。

import java.io.BufferedReader;import java.io.InputStream;import java.io.InputStreamReader;import java.io.PrintWriter;import java.math.BigInteger;import java.util.Arrays;import java.util.StringTokenizer;public class Main {public static void main(String[] args) {new Task().solve();}}class Task {InputReader in = new InputReader(System.in) ;PrintWriter out = new PrintWriter(System.out) ;final int N = 50 ; Tire tire = new Tire() ; void solve() {tire.clear() ; int[][] fib = new int[3][N] ;Arrays.fill(fib[0] , 0) ;Arrays.fill(fib[1] , 0) ;Arrays.fill(fib[2] , 0) ;fib[0][0] = 1 ;fib[1][0] = 1 ;tire.add(fib[0] , 0) ;  for(int n = 2 ; n < 100000 ; n++){int i = 0  , c = 0 ;for( ; i < N ; i++){fib[2][i] = (c + fib[1][i] + fib[0][i]) % 10 ;c = (c + fib[1][i] + fib[0][i]) / 10 ;}if(i == N && c > 0){for(int k = 0 ; k <= N-2 ; k++){fib[2][k] = fib[2][k+1] ;fib[1][k] = fib[1][k+1] ;}fib[2][N-1] = c ;fib[1][N-1] = 0 ;}for(int k = 0 ; k < N ; k++){fib[0][k] = fib[1][k] ;fib[1][k] = fib[2][k] ;}tire.add(fib[2] , n) ;}    int t = in.nextInt() ;    for(int cas = 1 ; cas <= t ; cas++){    out.println("Case #" + cas  + ": " + tire.find(in.next().toCharArray())) ;    }out.flush() ;}}class Tire{final int nodeSize = 100000*40 + 8 ;final int sonSize = 10 ;int[][] next = new int[nodeSize][sonSize] ;int[] lable = new int[nodeSize] ;int root , totel ;int newNode(){for(int i = 0 ; i < sonSize ; i++){next[totel][i] = 0 ;}lable[totel] = -1 ;return totel++ ;}void clear(){totel = 0 ;root = newNode() ;}void add(int[] word , int id){int now = root ;int i = word.length - 1 , len = 0  ;while(i >= 0 && word[i] == 0){i-- ;}while(i >= 0 && ++len <= 40){if(next[now][word[i]] == 0){next[now][word[i]] = newNode() ;}now = next[now][word[i]] ;if(lable[now] == -1){lable[now] = id ;}i-- ;}}int find(char[] word){int now = root ;for(char c : word){int i = c - '0' ;if(next[now][i] == 0){return -1  ;}now = next[now][i] ;}return lable[now] ; }}class InputReader {public BufferedReader reader;public StringTokenizer tokenizer;public InputReader(InputStream stream) {reader = new BufferedReader(new InputStreamReader(stream), 32768);tokenizer = new StringTokenizer("");}private void eat(String s) {tokenizer = new StringTokenizer(s);}public String nextLine() {try {return reader.readLine();} catch (Exception e) {return null;}}public boolean hasNext() {while (!tokenizer.hasMoreTokens()) {String s = nextLine();if (s == null)return false;eat(s);}return true;}public String next() {hasNext();return tokenizer.nextToken();}public int nextInt() {return Integer.parseInt(next());}public long nextLong() {return Long.parseLong(next());}public double nextDouble() {return Double.parseDouble(next());}public BigInteger nextBigInteger() {return new BigInteger(next());}}