神秘RE代码求调

#include<bits/stdc++.h>
using namespace std;
string s,s1;
int len,cnt=1,mr,mid,ans;
int l[100000010]; 
int main(){
	cin>>s;
	len=s.length();
	s=' '+s;
	s1[0]=' ',s1[1]='#'; 
	for(int i=1;i<=len;i++){
		s1[++cnt]=s[i];
		s1[++cnt]='#';
	}
	return 0; 
	for(int i=2;i<=cnt;i++){
		if(i<=mr)l[i]=min(l[mid*2-i],mr-i+1);
		else l[i]=1;
		while(s1[i-l[i]]==s1[i+l[i]])l[i]++;
		if(i+l[i]>mr){
			mr=i+l[i]-1,mid=i;
		}
		ans=max(ans,l[i]);
	}
	exit(0); 
	return 0;
}