//code by Emissary
#include<bits/stdc++.h>

#define fi first
#define se second
#define vc vector
#define db double
#define ll long long
#define mk make_pair
#define pb push_back
#define PI pair<int,int>
#define ull unsigned long long
#define err cerr << "   -_-   " << endl
#define debug cerr << " ------------------- " << endl

#define input(x) freopen(#x".in","r",stdin)
#define output(x) freopen(#x".out","w",stdout)

#define NO puts("No")
#define YES puts("Yes")

//#define int long long

using namespace std;

namespace IO{
	inline int read(){
		int X=0, W=0; char ch=getchar();
		while(!isdigit(ch)) W|=ch=='-', ch=getchar();
		while(isdigit(ch)) X=(X<<1)+(X<<3)+(ch^48), ch=getchar();
		return W?-X:X;
	}
	inline void write(int x){
		if(x<0) x=-x, putchar('-');
		if(x>9) write(x/10);
		putchar(x%10+'0');
	}
	inline void sprint(int x){write(x), putchar(32);}
	inline void eprint(int x){write(x), putchar(10);}
}using namespace IO;

const int MAXN = 5e5+5;

int n;
int a[MAXN], b[MAXN], c[MAXN];

vc<PI> ans[2];

inline void rev(int l, int r, int t){
	for(int i=l, j=r;i<j;++i, --j) ans[t].pb(mk(i,j)), swap(a[i],a[j]);
	return ;
}

inline void Merge(int l, int r, int t){
	int mid=(l+r)>>1, pos=l;
	int len=mid-l+1; vc<int> num;
	while(pos<r && a[pos]<a[pos+1]) ++pos;
	if(pos==r) return ;
	for(int i=l;i<=r;++i) num.pb(a[i]);
	sort(num.begin(),num.end()); int std_=num[len-1], L=n+1, R=0, vl=n+1, vr=0;
	for(int i=l;i<=pos;++i){
		if(a[i]>std_){
			L=i; vl=min(vl,i); vr=max(vr,pos);
			rev(i,pos,t);
			break;
		}
	}
	for(int i=r;i>pos;--i){
		if(a[i]<=std_){
			R=i; vr=max(vr,i); vl=min(vl,pos+1);
			rev(pos+1,i,t);
			break;
		}
	}
	if(vl<=vr) rev(vl,vr,t);
	Merge(l,mid,t); Merge(mid+1,r,t);
	return ;
}

inline void MergeSort(int l, int r, int t){
	if(l==r) return ;
	int mid=(l+r)>>1;
	MergeSort(l,mid,t); MergeSort(mid+1,r,t);
	Merge(l,r,t);
}

inline void op(int l, int r){
	int maxn=-1, maxpos, minn=n+1, minpos;
	for(int i=l;i<=r;++i) if(b[i]>maxn) maxn=b[i], maxpos=i;
	for(int i=l;i<=r;++i) if(b[i]<minn) minn=b[i], minpos=i;
	swap(b[minpos],b[maxpos]);
}

signed main(){
	n=read();
	for(int i=1;i<=n;++i) a[i]=read(), b[i]=a[i];
	MergeSort(1,n,0);
	for(int i=1;i<=n;++i) a[i]=read(), c[i]=a[i];
	MergeSort(1,n,1);
	eprint(ans[0].size()+ans[1].size());
	for(auto i:ans[0]) sprint(i.fi), eprint(i.se), op(i.fi,i.se);
	reverse(ans[1].begin(),ans[1].end());
	for(auto i:ans[1]) sprint(i.fi), eprint(i.se), op(i.fi,i.se);
	return 0;
}