#include<bits/stdc++.h>
using namespace std;


void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '\"' << x << '\"';}
void __print(const string &x) {cerr << '\"' << x << '\"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i : x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}

#define fo(i, n) for(int i=0; i<n; i++)
#define Fo(i, k, n) for(int i=k; i<n; i++)
#define w(x)  int x; cin>>x; while(x--)
#define watch(x) cout << (#x) << " is " << (x) << "\n"
#define watch2(x,y) cout <<(#x)<<" is "<<(x)<<" and "<<(#y)<<" is "<<(y)<<"\n"
#define watch3(x,y,z) cout <<(#x)<<" is "<<(x)<<" and "<<(#y)<<" is "<<(y)<<" and "<<(#z)<<" is "<<(z)<<"\n"
#define watch4(x,y,z,q) cout <<(#x)<<" is "<<(x)<<" and "<<(#y)<<" is "<<(y)<<" and "<<(#z)<<" is "<<(z)<<" and "<<(#q)<<" is "<<(q)<<"\n"
#define MOD 1000000007
#define INF 1000000007;
#define F first
#define S second
#define pb(x) push_back(x);


#define ll  long long
#define all(c) (c).begin(),(c).end()
#define endl "\n"

typedef vector<int> vl;
typedef vector< vl > vvl;
typedef pair< int, int> pll;
typedef map< int, int> mll;


#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif





void c_p_c()
{
#ifndef ONLINE_JUDGE
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
}
void parray(int a[], int n) {
	for (int i = 0; i < n; i++) {
		cout << a[i] << " ";
	}
	cout << endl;
}



int check(int n) {

	int temp = n + 9;

	temp = temp / 10;
	return temp * 10;



}

bool comp(pair<string, pair<int, int>> a , pair<string, pair<int, int>> b) {


	// return a % 10 > b % 10;
	if (a.F != b.F)
		return a.F < b.F;
	return a.S.F > b.S.F;

}
bool check(int a, int b, int c) {

	set<int> s;
	s.insert(a);
	s.insert(b);
	s.insert(c);

	auto it = s.begin();
	it++;
	// cout<<*it<<endl;
	if (b == *it)
		return true;
	return false;



}
bool isPerfectSquare(ll n) 
{ 
    for (ll i = 1; i * i <= n; i++) { 
  
        // If (i * i = n) 
        if ((n % i == 0) && (n / i == i)) { 
            return true; 
        } 
    } 
    return false; 
}

int main() {
	int i, n, m, k, c = 0;
	c_p_c();
	cin>>n;
	int a[n];
	int b[n];
	fo(i,n) cin>>a[i],b[i]=a[i];	

	sort(a,a+n);
	for (int i = 0; i < n; ++i)
	{
		/* code */
		if(a[i]!=b[i])
			c++;
	}
	if(c==0 || c==2)
		cout<<"YES"<<endl;
	else
		cout<<"NO"<<endl;

	return 0;
}



Measured memory_bytes: 3504