【kmp算法】bzoj1355 [Baltic2009]Radio Transmission

#include<cstdio>
#include<cstring>
using namespace std;
int next[1000001],n;
char s[1000001];
void GetFail(char P[],int next[])
{
next[0]=next[1]=0;
for(int i=1;i<n;i++)
{
int j=next[i];
while(j&&P[i]!=P[j]) j=next[j];
if(P[i]==P[j]) next[i+1]=j+1;
else next[i+1]=0;
}
}
int main()
{
scanf("%d",&n); scanf("%s",s);
GetFail(s,next);
printf("%d\n",n-next
);
return 0;
}