后缀自动机（SAM）模板

Code

void make()
{
int last=1;
fo(i,1,n)
{
int p=last,c=ch[i]-'A';
mx[last=++tot]=i;
while(p&&!t[p][c]) t[p][c]=ls,p=fail[p];
if(p)
{
int q=t[p][c];
if(mx[q]==mx[p]+1) fail[last]=q;
else
{
fail[++tot]=fail[q];
fail[last]=fail[q]=tot;
fo(j,0,25) t[tot][j]=t[q][j];
mx[tot]=mx[p]+1;
while(p&&t[p][c]==q) t[p][c]=tot,p=fail[p];
}
}
else fail[last]=1;
}
}