不懂就问

//可通过
#include<bits/stdc++.h>
using namespace std;
const int N=1e6+5;
string s1,s2;
int kmp[N];
int main(){
	cin>>s1>>s2;
	int r1=0;//s2前缀末尾 
	int len1=s1.length(),len2=s2.length();
	for(int r2=1;r2<len2;r2++){;//s2后缀末尾 
		while(r1>0&&s2[r1]!=s2[r2])	r1=kmp[r1-1];
		if(s2[r1]==s2[r2])	r1++;//最多前进一次 
		kmp[r2]=r1;
	}
	int l2=0;
	for(int l1=0;l1<=len1;l1++){
		while(l2>0&&s1[l1]!=s2[l2])	l2=kmp[l2-1];
		if(s1[l1]==s2[l2]){
		//	printf("(%d)",l2);
			l2++;
			if(l2==len2){
				printf("%d\n",l1-len2+2);
				l2=kmp[l2-1];
			}
			
			
		}
		//else l2=kmp[l2-1];
	} 
	for(int i=0;i<len2;i++)	printf("%d ",kmp[i]);
}

//不可通过
#include<bits/stdc++.h>
using namespace std;
const int N=1e6+5;
string s1,s2;
int next[N];
int main(){
	cin>>s1>>s2;
	int r1=0;//s2前缀末尾 
	int len1=s1.length(),len2=s2.length();
	for(int r2=1;r2<len2;r2++){;//s2后缀末尾 
		while(r1>0&&s2[r1]!=s2[r2])	r1=next[r1-1];
		if(s2[r1]==s2[r2])	r1++;//最多前进一次 
		next[r2]=r1;
	}
	int l2=0;
	for(int l1=0;l1<=len1;l1++){
		while(l2>0&&s1[l1]!=s2[l2])	l2=next[l2-1];
		if(s1[l1]==s2[l2]){
		//	printf("(%d)",l2);
			l2++;
			if(l2==len2){
				printf("%d\n",l1-len2+2);
				l2=next[l2-1];
			}
			
			
		}
		//else l2=kmp[l2-1];
	} 
	for(int i=0;i<len2;i++)	printf("%d ",next[i]);
}