// ~~ icebear ~~
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;
template<class T>
bool minimize(T &a, const T &b) {
if (a > b) return a = b, true;
return false;
}
template<class T>
bool maximize(T &a, const T &b) {
if (a < b) return a = b, true;
return false;
}
#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "icebear"
/*END OF TEMPLATE. ICEBEAR AND THE CAT WILL WIN VOI26 */
const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll INF = 1e18 + 27092008;
const int N = 5000 + 5;
int numTree;
struct Tree {
int x, y;
bool operator < (const Tree &other) const {
if (x == other.x) return y < other.y;
return x < other.x;
}
} tree[N];
void init(void) {
cin >> numTree;
FOR(i, 1, numTree) cin >> tree[i].x >> tree[i].y;
sort(tree + 1, tree + numTree + 1);
}
void process(void) {
int ans = 0;
FOR(i, 1, numTree) {
set<int> Y;
FOR(j, i + 1, numTree) {
int l = tree[i].y;
int r = tree[j].y;
if (l > r) swap(l, r);
auto it = Y.lower_bound(l);
if (it != Y.end() && it != Y.begin() && *it > r) {
auto prv = prev(it);
ans += 1LL * (tree[j].x - tree[i].x - 1) * (*it - *prv - 1) % MOD;
if (ans >= MOD) ans -= MOD;
}
Y.insert(tree[j].y);
}
}
cout << ans;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
if (fopen(task".inp", "r")) {
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
int tc = 1;
// cin >> tc;
while(tc--) {
init();
process();
}
return 0;
}
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