HDU(3374) （KMP + 最小表示法）

题目：http://acm.hdu.edu.cn/showproblem.php?pid=3374
最小表示法：http://tobyaa.blog.163.com/blog/static/30248591201261604349913/
#include <stdio.h>
#include <string.h>
#include <iostream>
#include <algorithm>
using namespace std;
const int maxn = 1000005;
char str[maxn];
int next[maxn];
void get_next(char str[],int next[]){
    int i = 0,j = -1;
    next[0] = -1;
    int len = (int)strlen(str);
    while(i < len){
        if(j == -1 || str[i] == str[j])
            next[++i] = ++j;
        else
            j = next[j];
    }
}
int getmin(char str[]){
    int len = (int)strlen(str);
    int i = 0,j = 1,k = 0;
    while(i < len && j < len && k < len){
        int t = str[(i + k)%len] - str[(j + k)%len];
        if(!t)
            k++;
        else{
            if(t < 0) j += k+1;
            else i += k+1;
            if(i == j) j++;
            k = 0;
        }
    }
    return i>j?j:i;
}
int getmax(char str[]){
    int len = (int)strlen(str);
    int i = 0,j = 1,k = 0;
    while(i < len && j < len && k < len){
        int t = str[(i + k)%len] - str[(j + k)%len];
        if(!t)
            k++;
        else{
            if(t > 0) j += k+1;
            else i += k+1;
            if(i == j) j++;
            k = 0;
        }
    }
    return i>j?j:i;
}
int main(){
    while(~scanf("%s",str)){
        get_next(str, next);
        int len = (int)strlen(str);
        int time = 1;
        if(len%(len - next[len]) == 0)
            time = len/(len - next[len]);
        printf("%d %d %d %d\n",getmin(str)+1,time,getmax(str)+1,time);
    }
    return 0;
}