题目链接: https://codeforces.com/contest/432/problem/D
题解L
做法一: KMP
显然next树上\(n\)的所有祖先都是答案,出现次数为next树子树大小。
做法二: 后缀数组
按照height分组,二分查找即可。
代码
KMP:
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<vector>
#include<utility>
using namespace std;
const int N = 1e5;
char a[N+3];
int nxt[N+3];
int sz[N+3];
vector<pair<int,int> > ans;
int n;
void KMP()
{
nxt[0] = nxt[1] = 0;
for(int i=2; i<=n; i++)
{
nxt[i] = nxt[i-1];
while(nxt[i] && a[nxt[i]+1]!=a[i])
{
nxt[i] = nxt[nxt[i]];
}
if(a[nxt[i]+1]==a[i]) nxt[i]++;
}
}
int main()
{
scanf("%s",a+1); n = strlen(a+1);
for(int i=1; i<n+1-i; i++) swap(a[i],a[n+1-i]);
KMP();
for(int i=1; i<=n; i++) sz[i] = 1;
for(int i=n; i>=1; i--) sz[nxt[i]] += sz[i];
for(int i=n; i>0; i=nxt[i])
{
ans.push_back(make_pair(i,sz[i]));
}
printf("%d\n",ans.size());
for(int i=ans.size()-1; i>=0; i--) printf("%d %d\n",ans[i].first,ans[i].second);
return 0;
}
原文地址:https://www.cnblogs.com/suncongbo/p/11043339.html
时间: 2024-10-28 20:24:33