import std.stdio, std.array, std.string, std.conv, std.algorithm;
import std.typecons, std.range, std.random, std.math, std.container;
import std.numeric, std.bigint, core.bitop;


void main() {
    auto N = readln.chomp.to!int;
    auto A = readln.split.map!(x => x.to!int-1).array;
    auto cnt = N.iota.map!(i => i == A[i]).sum;
    writeln( N - cnt == 2 ? "NO" : "YES" );
}