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

using ll=long long;
#define int ll

#define rng(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,b) rng(i,0,b)
#define gnr(i,a,b) for(int i=int(b)-1;i>=int(a);i--)
#define per(i,b) gnr(i,0,b)
#define pb push_back
#define eb emplace_back
#define a first
#define b second
#define bg begin()
#define ed end()
#define all(x) x.bg,x.ed
#ifdef LOCAL
#define dmp(x) cerr<<__LINE__<<" "<<#x<<" "<<x<<endl
#else
#define dmp(x) void(0)
#endif

template<class t,class u> void chmax(t&a,u b){if(a<b)a=b;}
template<class t,class u> void chmin(t&a,u b){if(b<a)a=b;}

template<class t> using vc=vector<t>;
template<class t> using vvc=vc<vc<t>>;

using pi=pair<int,int>;
using vi=vc<int>;

template<class t,class u>
ostream& operator<<(ostream& os,const pair<t,u>& p){
	return os<<"{"<<p.a<<","<<p.b<<"}";
}

template<class t> ostream& operator<<(ostream& os,const vc<t>& v){
	os<<"{";
	for(auto e:v)os<<e<<",";
	return os<<"}";
}

#define mp make_pair
#define mt make_tuple
#define one(x) memset(x,-1,sizeof(x))
#define zero(x) memset(x,0,sizeof(x))
#ifdef LOCAL
void dmpr(ostream&os){os<<endl;}
template<class T,class... Args>
void dmpr(ostream&os,const T&t,const Args&... args){
	os<<t<<" ";
	dmpr(os,args...);
}
#define dmp2(...) dmpr(cerr,"Line:",__LINE__,##__VA_ARGS__)
#else
#define dmp2(...) void(0)
#endif

using uint=unsigned;
using ull=unsigned long long;

template<int i,class T>
void print_tuple(ostream&,const T&){
}

template<int i,class T,class H,class ...Args>
void print_tuple(ostream&os,const T&t){
	if(i)os<<",";
	os<<get<i>(t);
	print_tuple<i+1,T,Args...>(os,t);
}

template<class ...Args>
ostream& operator<<(ostream&os,const tuple<Args...>&t){
	os<<"{";
	print_tuple<0,tuple<Args...>,Args...>(os,t);
	return os<<"}";
}

void print(ll x,int suc=1){
	cout<<x;
	if(suc==1)
		cout<<"\n";
	if(suc==2)
		cout<<" ";
}

ll read(){
	ll i;
	cin>>i;
	return i;
}

vi readvi(int n,int off=0){
	vi v(n);
	rep(i,n)v[i]=read()+off;
	return v;
}

template<class T>
void print(const vector<T>&v,int suc=1){
	rep(i,v.size())
		print(v[i],i==int(v.size())-1?suc:2);
}

string readString(){
	string s;
	cin>>s;
	return s;
}

template<class T>
T sq(const T& t){
	return t*t;
}

//#define CAPITAL
void yes(bool ex=true){
	#ifdef CAPITAL
	cout<<"YES"<<endl;
	#else
	cout<<"Yes"<<endl;
	#endif
	if(ex)exit(0);
}
void no(bool ex=true){
	#ifdef CAPITAL
	cout<<"NO"<<endl;
	#else
	cout<<"No"<<endl;
	#endif
	if(ex)exit(0);
}

constexpr ll ten(int n){
	return n==0?1:ten(n-1)*10;
}

const ll infLL=LLONG_MAX/3;

#ifdef int
const int inf=infLL;
#else
const int inf=INT_MAX/2-100;
#endif

int topbit(signed t){
	return t==0?-1:31-__builtin_clz(t);
}
int topbit(ll t){
	return t==0?-1:63-__builtin_clzll(t);
}
int botbit(signed a){
	return a==0?32:__builtin_ctz(a);
}
int botbit(ll a){
	return a==0?64:__builtin_ctzll(a);
}
int popcount(signed t){
	return __builtin_popcount(t);
}
int popcount(ll t){
	return __builtin_popcountll(t);
}
bool ispow2(int i){
	return i&&(i&-i)==i;
}
int mask(int i){
	return (int(1)<<i)-1;
}

bool inc(int a,int b,int c){
	return a<=b&&b<=c;
}

template<class t> void mkuni(vc<t>&v){
	sort(all(v));
	v.erase(unique(all(v)),v.ed);
}

ll rand_int(ll l, ll r) { //[l, r]
	#ifdef LOCAL
	static mt19937_64 gen;
	#else
    static random_device rd;
    static mt19937_64 gen(rd());
    #endif
    return uniform_int_distribution<ll>(l, r)(gen);
}

template<class t>
int lwb(const vc<t>&v,const t&a){
	return lower_bound(all(v),a)-v.bg;
}

signed main(){
	cin.tie(0);
	ios::sync_with_stdio(0);
	cout<<fixed<<setprecision(20);
	
	int n;cin>>n;
	
	auto chk=[&](vi p){
		rep(i,n)if(p[i]%2!=i%2)return 0;
		
		vi to(n);
		rep(i,n)to[p[i]]=i;
		
		int a=-1,b=-1;
		vi u(n);
		rep(i,n)if(to[i]<i){
			u[i]=1;
			if(to[i]<b){
				if(to[i]<a)
					return 0;
				if(i%2!=b%2)
					return 0;
			}
			tie(a,b)=pi(to[i],i);
		}
		vi z[2];
		rep(i,n)if(!u[p[i]])
			z[i%2].pb(p[i]);
		rep(k,2)
			if(!is_sorted(all(z[k])))return 0;
		return 1;
	};
	
	vi p=readvi(n,-1);
	
	if(chk(p))yes();
	else no();
	
	/*vvc<int> dp(n,vi(n));
	vi ans(n);
	ans[0]=1;
	rng(i,1,n){
		ans[i]=ans[i-1];
		for(int j=i%2;j<i;j+=2){
			dp[i][j]=ans[j];
			for(int k=i-2;k>j;k-=2){
				for(int l=k%2;l<j;l+=2){
					dp[i][j]+=dp[k][l];
				}
			}
			ans[i]+=dp[i][j];
		}
	}
	cout<<ans<<endl;*/
	
	/*set<vi> vis;
	vvc<int> st;
	auto rc=[&](vi p){
		if(vis.count(p))return;
		vis.insert(p);
		st.pb(p);
	};
	
	{
		vi p(n);
		iota(all(p),0);
		rc(p);
	}
	
	while(st.size()){
		vi p=st.back();st.pop_back();
		rep(i,n-2){
			if(p[i]<p[i+1]&&p[i+1]<p[i+2]){
				swap(p[i],p[i+2]);
				rc(p);
				swap(p[i],p[i+2]);
			}
		}
	}
	
	cout<<vis.size()<<endl;
	
	vi p(n);
	iota(all(p),0);
	do{
		int c=vis.count(p);
		int d=chk(p);
		if(c!=d){
			cout<<c<<" "<<d<<endl;
			cout<<p<<endl;
		}
		assert(c==d);
	}while(next_permutation(all(p)));*/
	
	/*map<vi,vvc<int>> z;
	for(auto p:vis){
		vi tmp;
		for(int i=0;i<n;i+=2)
			tmp.pb(p[i]);
		z[tmp].pb(p);
	}
	for(auto kv:z){
		cout<<kv.a<<endl;
		cout<<kv.b.size()<<endl;
		for(auto w:kv.b)
			cout<<w<<endl;
		cout<<endl;
	}*/
}


Measured memory_bytes: 13032