#pragma GCC optimize("Ofast,unroll-loops")
#include<bits/stdc++.h>
//#define int long long
//#define ll long long
#define down cout<<'\n';
#define debug cout<<" cucuucucuuu",down
#define NHP ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
#define modwwe int t;cin>>t; while(t--)
#define bit(i,j) (i>>j&1)
#define sobit(a) __builtin_popcountll(a)
#define task "test"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define pb push_back
#define checktime cerr << (double)clock() / CLOCKS_PER_SEC * 1000 << " ms";
using namespace std;
#define getchar_unlocked getchar
inline int scan()
{
char c = getchar_unlocked();
int x = 0;
while (c < '0' || c > '9')
{
c = getchar_unlocked();
}
while (c >= '0' && c <= '9')
{
x = (x << 1) + (x << 3) + c - '0';
c = getchar_unlocked();
}
return x;
}
void phongbeo();
const int inf = 1e17;
const int mod2 = 1e9 + 9;
const int mod1 = 998244353;
struct icd
{
long double a;
int b;
};
struct ib
{
int a;
int b;
};
struct ic
{
int a, b, c;
};
struct id
{
int a, b, c, d;
};
struct ie
{
int a, b, c, d, e;
};
int n, m, s1, s2, s4, s3, sf, k, s5, s6, mx, s7, s8, s9, mx2, res, dem2 = 0, dem = 0, s33, dem3, dem4, l, r, mid, l2, r2, center;
int i, s10, s12,k1,k2,s11;
int kk;
int el = 19;
main()
{
if(fopen(task".inp","r"))
{
fin(task);
fou(task);
}
NHP
/// cin>>s1;
///modwwe
phongbeo();
// checktime
}
vector<int> v[2001];
ib a[2001];
int c[2001];
bool cmp(ib a,ib b)
{
return a.a<b.a;
}
void dfs(int x)
{
for(auto f:v[x])
{
if(c[f]==c[x]){cout<<0; exit(0);}
if(!c[f]){
c[f]=3-c[x];
dfs(f);
}
}
}
void phongbeo()
{
cin>>n;
for(int i=1;i<=n;i++)
cin>>a[i].a>>a[i].b;
for(int i=1;i<n;i++)
for(int j=i+1;j<=n;j++){
if(a[i].a>a[j].b||a[j].a>a[i].b)
continue;
if(a[i].a>=a[j].a&&a[i].b<=a[j].b) continue;
if(a[j].a>=a[i].a&&a[j].b<=a[i].b) continue;
v[i].pb(j);
v[j].pb(i);
}
s4=1;
for(int i=1;i<=n;i++)
if(!c[i])
{
c[i]=1;
s4=s4*2;
dfs(i);
}
cout<<s4;
}
