为啥TLE啊，啥事TLE啊。求解答。

只TLE了一个点，很难受，求大佬帮忙，sa做的

//#pragma GCC optimize("Ofast","-funroll-loops","-fdelete-null-pointer-checks")
//#pragma GCC target("ssse3","sse3","sse2","sse","avx2","avx")
#include<bits/stdc++.h>
#define int long long
using namespace std;

int read() {
	char ch=getchar();
	int f=1,x=0;
	while(ch<'0'||ch>'9') {
		if(ch=='-')
			f=-1;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9') {
		x=x*10+ch-'0';
		ch=getchar();
	}
	return f*x;
}

const int maxn=1e6+10;

int n,sa[maxn],a[maxn],t[maxn],b[maxn],c[maxn],rnk[maxn],m,w[maxn];
string s;

void bucket_sort(int v[]) {
	fill(c,c+m+1,0); 
	for(int i=1;i<=n;i++) {
		c[v[i]+1]++;
	}
	for(int i=1;i<=m;i++) {
		c[i]+=c[i-1];
	}
	for(int i=1;i<=n;i++) {
		t[++c[v[sa[i]]]]=sa[i];
	}
	for(int i=1;i<=n;i++) {
		sa[i]=t[i];
	}
}

void get_rnk() {
	m=0;
	for(int i=1;i<=n;i++) {
		if(a[sa[i]]!=a[sa[i-1]]||b[sa[i]]!=b[sa[i-1]]) {
			m++;
		}
		rnk[sa[i]]=m;
	}
}

void suffix_array() {
	for(int i=1;i<=n;i++) {
		a[i]=w[i];
		b[i]=0;
		sa[i]=i;
	}
	bucket_sort(a);
	get_rnk();
	
	for(int l=1;l<n;l<<=1) {
		for(int i=1;i<=n;i++) {
			a[i]=rnk[i];
			if(i+l<=n) {
				b[i]=rnk[i+l];
			}
			else{
				b[i]=0;
			}
		}
		
		bucket_sort(b);
		bucket_sort(a);
		get_rnk(); 
	}
}

signed main() {
	//freopen(".in","r",stdin);
	//freopen(".out","w",stdout);
	
	n=read();
	m=0;
	for(int i=1;i<=n;i++) {
		char c;
		cin>>c;
		w[i]=w[n*2-i+1]=(int)c;
		m=max(m,w[i]);
	}
	
	n<<=1;
	suffix_array();
	
	n>>=1;
	int l=1,r=n;
	for(int i=1;i<=n;i++) {
		if(w[l]<w[r]) {
			printf("%c",w[l]);
			l++;
		}
		else if(w[l]>w[r]) {
			printf("%c",w[r]);
			r--;
		}
		else {
			if(rnk[l]<rnk[n*2-r+1]) {
				printf("%c",w[l]);
				l++;
			}
			else {
				printf("%c",w[r]);
				r--;
			}
		}
		if(i%80==0) {
			cout<<endl;
		}
	}

	//fclose(stdin);
	//fclose(stdout);
	return 0;
}