HDU 3746 Cyclic Nacklace KMP

KMP算法——

AC代碼：

 
#include <iostream>   
#include <cstdio>   
#include <cstdlib>   
#include <cmath>   
#include <cstring>   
#include <string>   
#include <vector>   
#include <list>   
#include <deque>   
#include <queue>   
#include <iterator>   
#include <stack>   
#include <map>   
#include <set>   
#include <algorithm>   
#include <cctype>   
using namespace std;  
  
typedef long long LL;  
const int N=200005;  
const LL II=100000000;  
const int INF=0x3f3f3f3f;  
const double PI=acos(-1.0);  
  
int next[N],len,nextval[N];  
char str[N];  
  
void getnext(char *p)  
{  
    int j=0,k=-1;  
    next[0]=-1;  
    while(j<len)//len是p的長度   
    {  
        if(k==-1||p[j]==p[k])  
        {  
            j++;    k++;  
            next[j]=k;  
        }  
        else  
            k=next[k];  
    }  
}  
  
void getnextval(const char *p)  
{  
    int i = 0,j =-1;  
    nextval[0]=-1;  
    while(i!=len)  
    {  
        if(j==-1||p[i]==p[j])  
        {  
            ++i;++j;  
            if(p[i]!=p[j])  
                nextval[i]=j;  
            else  
                nextval[i]=nextval[j];  
        }  
        else  
            j=nextval[j];  
    }  
}  
  
int main()  
{  
    int i,j,T;  
    cin>>T;  
    while(T--)  
    {  
        scanf("%s",str);  
        len=strlen(str);  
        getnext(str);  
        int min_repeat=len-next[len];  
        if(min_repeat==len)  
            printf("%d\n",len);  
        else if(len%min_repeat==0)  
            printf("0\n");  
        else  
            printf("%d\n",min_repeat-len%min_repeat);  
    }  
    return 0;  
}  

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <queue>
#include <iterator>
#include <stack>
#include <map>
#include <set>
#include <algorithm>
#include <cctype>
using namespace std;

typedef long long LL;
const int N=200005;
const LL II=100000000;
const int INF=0x3f3f3f3f;
const double PI=acos(-1.0);

int next[N],len,nextval[N];
char str[N];

void getnext(char *p)
{
    int j=0,k=-1;
    next[0]=-1;
    while(j<len)//len是p的長度
    {
        if(k==-1||p[j]==p[k])
        {
            j++;    k++;
            next[j]=k;
        }
        else
            k=next[k];
    }
}

void getnextval(const char *p)
{
    int i = 0,j =-1;
    nextval[0]=-1;
    while(i!=len)
    {
        if(j==-1||p[i]==p[j])
        {
            ++i;++j;
            if(p[i]!=p[j])
                nextval[i]=j;
            else
                nextval[i]=nextval[j];
        }
        else
            j=nextval[j];
    }
}

int main()
{
    int i,j,T;
    cin>>T;
    while(T--)
    {
        scanf("%s",str);
        len=strlen(str);
        getnext(str);
        int min_repeat=len-next[len];
        if(min_repeat==len)
            printf("%d\n",len);
        else if(len%min_repeat==0)
            printf("0\n");
        else
            printf("%d\n",min_repeat-len%min_repeat);
    }
    return 0;
}