复杂度带log的同学们注意了,其实双log也能过!
大致思想是stable_sort套上二分哈希值
#include<bits/stdc++.h>
using namespace std;
const int N=1e6+10;
char s[N];
#define ull unsigned long long
ull h[N],Pow[N],base=131;
int a[N];
int n;
ull f(int l,int r)
{
return h[r]-h[l-1]*Pow[r-l+1];
}
bool cmp(int x,int y)
{
bool op=0;
if(x>y)
op=1,swap(x,y);
int l=1,r=y-x,ans=0; //后面相同的位数
while(l<=r)
{
int mid=(l+r)>>1;
if(f(x+1,x+mid)==f(x,x+mid-1))
ans=mid,l=mid+1;
else
r=mid-1;
}
if(x+ans==y)
return (x<y)^op;
else
return (s[x+ans+1]<s[x+ans])^op;
}
int main()
{
freopen("a.in","r",stdin);
freopen("a.out","w",stdout);
ios::sync_with_stdio(false);
cin.tie(0),cout.tie(0);
cin>>n;
for(int i=1;i<=n;i++)
cin>>s[i];
Pow[0]=1;
for(int i=1;i<=n;i++)
Pow[i]=Pow[i-1]*base;
for(int i=1;i<=n;i++)
h[i]=h[i-1]*base+s[i];
for(int i=1;i<=n;i++)
a[i]=i;
stable_sort(a+1,a+1+n,cmp);
for(int i=1;i<=n;i++)
cout<<a[i]<<' ';
return 0;
}