kmp跑两串的最大相同前后缀 HDU2594

  1 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);
  2 #include <cstdio>//sprintf islower isupper
  3 #include <cstdlib>//malloc  exit strcat itoa system("cls")
  4 #include <iostream>//pair
  5 #include <fstream>//freopen("C:\\Users\\13606\\Desktop\\Input.txt","r",stdin);
  6 #include <bitset>
  7 //#include <map>
  8 //#include<unordered_map>
  9 #include <vector>
 10 #include <stack>
 11 #include <set>
 12 #include <string.h>//strstr substr strcat
 13 #include <string>
 14 #include <time.h>// srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;
 15 #include <cmath>
 16 #include <deque>
 17 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less
 18 #include <vector>//emplace_back
 19 //#include <math.h>
 20 #include <cassert>
 21 #include <iomanip>
 22 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor
 23 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)
 24 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation
 25 //******************
 26 clock_t __STRAT,__END;
 27 double __TOTALTIME;
 28 void _MS(){__STRAT=clock();}
 29 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}
 30 //***********************
 31 #define rint register int
 32 #define fo(a,b,c) for(rint a=b;a<=c;++a)
 33 #define fr(a,b,c) for(rint a=b;a>=c;--a)
 34 #define mem(a,b) memset(a,b,sizeof(a))
 35 #define pr printf
 36 #define sc scanf
 37 #define ls rt<<1
 38 #define rs rt<<1|1
 39 typedef pair<int,int> PII;
 40 typedef vector<int> VI;
 41 typedef long long ll;
 42 const double E=2.718281828;
 43 const double PI=acos(-1.0);
 44 const ll INF=(1LL<<60);
 45 const int inf=(1<<30);
 46 const double ESP=1e-9;
 47 const int mod=(int)1e9+7;
 48 const int N=(int)1e6+10;
 49 
 50 int key[N];
 51 int nxt[N];
 52 
 53 void getNext(int klen)
 54 {
 55     int j,k;
 56     j=0;
 57     k=-1;
 58     nxt[0]=-1;
 59     while(j<klen)
 60     {
 61         if(k==-1||key[j]==key[k])
 62         {
 63             nxt[++j]=++k;
 64             if(key[j]!=key[k])//优化
 65                 nxt[j]=k;
 66         }
 67         else
 68             k=nxt[k];
 69     }
 70 }
 71 template<class T>
 72 void PR(T _[],int n)
 73 {
 74     for(int i=0;i<=n;++i)
 75     {
 76         cout<<_[i];
 77         if(i==n)cout<<endl;
 78         else cout<<‘ ‘;
 79     }
 80 }
 81 char s1[N],s2[N];
 82 int main()
 83 {
 84     while(~sc("%s",s1))
 85     {
 86         sc("%s",s2);
 87         int len=strlen(s1);
 88         s1[len++]=‘#‘;s1[len++]=‘%‘;
 89         s1[len]=‘\0‘;
 90         strcat(s1,s2);
 91         len=strlen(s1);
 92         s1[len++]=‘$‘;
 93         s1[len]=‘\0‘;
 94         for(int i=0;i<len;++i)
 95             key[i]=s1[i];
 96         getNext(len);
 97         int ans=nxt[len-1];
 98         if(s1[ans]==s1[len-1])ans++;
 99         if(ans==0)
100         {
101             pr("0\n");
102             continue;
103         }
104         int len2=strlen(s2);
105         pr("%s %d\n",s2+len2-ans,ans);
106 //        PR(nxt,len-1);
107     }
108     return 0;
109 }
110 
111 /**************************************************************************************/