F - The Minimum Length

F - The Minimum Length

 HUST - 1010 

#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
int len;
char s[1000010];
int net[1000010];
void getnet(){
    memset(net,0,sizeof(net));
    net[0]=-1;
    int k=-1,j=0;
    while(j<len){
        if(k==-1||s[k]==s[j]){
            j++;k++;
            net[j]=k;
        }
        else k=net[k];
    }
}
int main(){
    while(scanf("%s",s)!=EOF){
        len=strlen(s);
        getnet();
        int tmp=len-net[len];
        printf("%d\n",tmp);
    }
}