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#include<cstdio>
#include<algorithm>
#define S 500007
#define M 1048576
#define C 22
using namespace std;
typedef long long ll;

int A[S];
int B[S];

int tree[2*M+7];

void sett(int l, int r, int ll, int rr, int w, int c){
    if(l > rr || r < ll)
        return;
    if(l >= ll && r <= rr){
        tree[w] = c;
        return;
    }
    int sr = (l+r)/2;
    sett(l,sr,ll,rr,w*2,c);
    sett(sr+1,r,ll,rr,w*2+1,c);
}

int gett(int x){
    x = x+M-1;
    int ans = 0;
    while(x != 0){
        ans = max(ans, tree[x]);
        x/=2;
    }
    return ans;
}

int L[S][C+1];
int R[S][C+1];

//TODO: make it ll
ll reachability[S];

int LCA(int l, int r){
    int p = l;
    int q = r;
    if(A[r] < B[l]){
        return min(l,r);
    }
    int x = C;
    int y = C;
    while(1){
        if(x == -1 && y == -1){
            if(A[r] < B[l]){
                return min(l,r);
            }else{
                return L[r][0];
            }
        }
        
        if(x == -1){
            if(L[r][y] > l || A[L[r][y]] > B[l]){
                r = L[r][y];
            }
            y--;
        }else if(y == -1){
            if(R[l][x] > r || B[R[l][x]] < A[r]){
                l = R[l][x];
            }
            x--;
        }else if(A[L[r][y]] < B[R[l][x]]){
            if(L[r][y] < R[l][x]){
                y--;
            }else{
                x--;
            }
        }else{
            if(L[r][y] > R[l][x]){
                r = L[r][y];
                y--;
            }else{
                l = R[l][x];
                x--;
            }
        }
    }
}

ll mod = 1000000007;
ll inv[S];

int main(void){
    inv[1] = 1;
    for(int i = 2; i < S; i++){
        inv[i] = (-(mod / (ll)i) * inv[mod % i]) % mod;
        inv[i] += mod;
    }
    int n;
    scanf("%d", &n);
    for(int i = 1; i <= n; i++){
        scanf("%d %d",&A[i+1], &B[i+1]);
        A[i+1]++;
        B[i+1]++;
    }
    n++;

    A[1] = 1;
    B[1] = 2*n;

    for(int j = 0; j <= C; j++){
        L[1][j] = 1;
        R[1][j] = 1;
    }
    
    sett(1,M,A[1],B[1],1,1);

    for(int i = 2; i <= n; i++){
        L[i][0] = gett(A[i]);
        R[i][0] = gett(B[i]);
        sett(1,M,A[i],B[i],1,i);
        for(int j = 1; j <= C; j++){
            L[i][j] = L[L[i][j-1]][j-1];
            R[i][j] = R[R[i][j-1]][j-1];
        }
    }
    
    for(int i = n; i >= 2; i--){
        reachability[i]++;

        int l = L[i][0];
        int r = R[i][0];

        int x = LCA(l, r);

        // printf("%d %d %d %d*\n",i,l,r,x);

        reachability[l] += reachability[i];
        reachability[r] += reachability[i];
        reachability[x] -= reachability[i];
    }
    
    ll ans = 0;
    for(int i = 2; i <= n; i++){
        ans += inv[reachability[i]];
        // printf("%d ", reachability[i]);
    }
    ans %= mod;
    printf("%lld\n",ans);


    return 0;
}