【練習03】 KMP 1004 Period

kmp，依次求字串首碼的最小迴圈節， AC耗時500ms，但是在statistic裡看到有人50msAC，

可能原因：

1.輸入輸出的最佳化

2.用了更神奇的演算法。

//模板開始#include <string>   #include <vector>   #include <algorithm>   #include <iostream>   #include <sstream>   #include <fstream>   #include <map>   #include <set>   #include <cstdio>   #include <cmath>   #include <cstdlib>   #include <ctime>#include<iomanip>#include<string.h>#define SZ(x) (int(x.size()))using namespace std;int toInt(string s){istringstream sin(s); int t; sin>>t; return t;}template<class T> string toString(T x){ostringstream sout; sout<<x; return sout.str();}typedef long long int64;int64 toInt64(string s){istringstream sin(s); int64 t; sin>>t;return t;}template<class T> T gcd(T a, T b){ if(a<0) return gcd(-a, b);if(b<0) return gcd(a, -b);return (b == 0)? a : gcd(b, a % b);}//模板結束（通用部分）//【練習03】 KMP 1004 Period#define ifs cin#define MAX_SIZE 10000005void getFail(char* P, int* f){int m = strlen(P);f[0] = 0;f[1] = 0;for(int i = 1; i < m; i++){int j = f[i];while(j && P[i] != P[j]){j = f[j];}f[i + 1]=P[i]==P[j]?j+1:0;if(f[i + 1] && (i + 1) % ((i + 1) - f[i + 1]) == 0)//KMP程式這裡有做改動{cout<<i + 1<<" "<<(i + 1) / ((i + 1) - f[i + 1])<<endl;}}}void find(char* T, char*P, int*f){int n = strlen(T), m = strlen(P);getFail(P, f);int j = 0;for(int i = 0; i < n; i++){while(j && P[j] != T[i]){j = f[j];}if(P[j] == T[i]){j++;}if(j == m){cout<<i - m + 1<<endl;}}}int main(){//ifstream ifs("shuju.txt", ios::in);int n;char* P = new char[MAX_SIZE];int* f = new int[MAX_SIZE];int str_len = strlen(P);static int count = 1;while(ifs>>n && n != 0){ifs>>P;cout<<"Test case #"<<count++<<endl;getFail(P, f);cout<<endl;}return 0;}