#include #include using std::cin; using std::cout; const char endl = '\n'; const int N = 1e5 + 5; const int mod = 1e9 + 7; int n, s[N << 1], f[N]; std::pair a[N]; int pow(int a, int b) { int res = 1; while (b) { if (b & 1) res = 1ll * res * a % mod; a = 1ll * a * a % mod; b >>= 1; } return res; } int main() { std::ios::sync_with_stdio(false); cin.tie(nullptr); cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i].first >> a[i].second; s[a[i].second]++; } std::sort(a + 1, a + 1 + n); for (int i = 1; i <= n << 1; i++) { s[i] += s[i - 1]; } for (int i = 1; i <= n; i++) { f[i] = (f[i - 1] * 2 % mod + pow(2, s[a[i].first - 1]) % mod) % mod; } cout << f[n] << endl; return 0; }