You are given a sequence a1, a2, ..., an of one-dimensional segments numbered 1 through n. Your task is to find two distinct indices i and j such that segment ai lies within segment aj.

Segment [l1, r1] lies within segment [l2, r2] iff l1 ≥ l2 and r1 ≤ r2.

Print indices i and j. If there are multiple answers, print any of them. If no answer exists, print -1 -1.

Input

The first line contains one integer n (1 ≤ n ≤ 3·105) — the number of segments.

Each of the next n lines contains two integers li and ri (1 ≤ li ≤ ri ≤ 109) — the i-th segment.

Output

Print two distinct indices i and j such that segment ai lies within segment aj. If there are multiple answers, print any of them. If no answer exists, print -1 -1.

Examples

Input

5
1 10
2 9
3 9
2 3
2 9


Output

2 1


Input

3
1 5
2 6
6 20


Output

-1 -1

Note

In the first example the following pairs are considered correct:

  * (2, 1), (3, 1), (4, 1), (5, 1) — not even touching borders; 
  * (3, 2), (4, 2), (3, 5), (4, 5) — touch one border; 
  * (5, 2), (2, 5) — match exactly. 
    //    A Computer is Like a mischievous genie.
    //    It will give you exactly what you ask for,
    //    but not always what you want
    //    A code by Rahul Verma


    import java.io.BufferedOutputStream;
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.io.PrintWriter;
    import java.math.BigInteger;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.Comparator;
    import java.util.HashMap;
    import java.util.HashSet;
    import java.util.LinkedHashSet;
    import java.util.LinkedList;
    import java.util.List;
    import java.util.PriorityQueue;
    import java.util.Queue;
    import java.util.Set;
    import java.util.Stack;
    import java.util.StringTokenizer;
    import java.util.TreeMap;
    import java.util.TreeSet;


    public class Main {


        static class Clock {

            protected long start, stop;

            public void start() {

                start = System.currentTimeMillis();
            }

            public void stop() {
                stop = System.currentTimeMillis();
            }

            public String getTime() {

                return ((stop - start) + " ms");
            }
        }


        public static PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));

        static class FastReader {

            BufferedReader br;
            StringTokenizer st;

            public FastReader() {
                br = new BufferedReader(new
                    InputStreamReader(System.in));
            }

            String next() {
                while (st == null || !st.hasMoreElements()) {
                    try {
                        st = new StringTokenizer(br.readLine());
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                return st.nextToken();
            }

            int nextInt() {
                return Integer.parseInt(next());
            }

            long nextLong() {
                return Long.parseLong(next());
            }

            double nextDouble() {
                return Double.parseDouble(next());
            }

            String[] nextSArray() {
                String sr[] = null;
                try {
                    sr = br.readLine().trim().split(" ");
                } catch (IOException e) {
                    e.printStackTrace();
                }
                return sr;
            }

            String nextLine() {
                String str = "";
                try {
                    str = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }

                return str;
            }
        }


        static long powmodulo(long a, long p) {
            if (p == 0) {
                return 1 % mod;
            }
            if (p == 1) {
                return a % mod;
            }
            long ans = 1;
            while (p > 0) {
                if ((p & 1) > 0) {
                    ans = (ans * a) % mod;
                }
                a = (a * a) % mod;
                p = p >> 1;
            }
            return ans % mod;
        }


        static long mod = 1000000007;

        static long gcd(long a, long b) {
            if (a == 0) {
                return b;
            }
            return gcd(b % a, a);
        }

        static long fast_powerNumbers(long a, long n) {
            if (n == 1) {
                return a;
            }
            long ans = fast_powerNumbers(a, n / 2);
            if (n % 2 == 0) {
                return (ans * ans);
            } else {
                return ((ans * ans) * (a));
            }
        }


        static void dfs_helper(int[][] arr, int i, int j, int team, int n, int m) {
            arr[i][j] = team;
            if (i - 1 >= 0 && arr[i - 1][j] == 1) {
                dfs(arr, i - 1, j, team, n, m);
            }
            if (j - 1 >= 0 && arr[i][j - 1] == 1) {
                dfs(arr, i, j - 1, team, n, m);
            }
            if (i + 1 < n && arr[i + 1][j] == 1) {
                dfs(arr, i + 1, j, team, n, m);
            }
            if (j + 1 < m && arr[i][j + 1] == 1) {
                dfs(arr, i, j + 1, team, n, m);
            }

        }

        static void dfs(int[][] arr, int i, int j, int team, int n, int m) {
            dfs_helper(arr, i, j, team, n, m);

        }
        public static int arr[];


        static void seive(int n) {
            // 1 is not prime
            arr = new int[n + 1];
            arr[0] = arr[1] = 1;
            for (int i = 4; i <= n; i = i + 2) {
                arr[i] = 1;
            }
            for (int i = 3; i * i <= n; i = i + 2) {
                if (arr[i] == 0) {
                    for (int j = i * i; j <= n; j = j + i) {
                        arr[j] = 1;
                    }

                }
            }
        }


        public static HashMap<Integer,Integer> primefac(int n)
        {
            HashMap<Integer,Integer>hm=new HashMap<>();
            //int x = (int) Math.sqrt(n);
            for (int i = 2; i <=n; i++) {
                int x=0;
                while(n%i==0)
                {
                    n=n/i;
                    ++x;
                }
                if(x!=0)
                {
                    hm.put(i,x);
                }
            }
            return hm;
        }
       static long fac(int p)
       {
           if(p==0||p==1)
               return 1;
           return p*fac(p-1);
       }


        public static void main(String[] args) throws Exception {
            FastReader sc = new FastReader();

            Clock clock = new Clock();

            clock.start();
          int n = sc.nextInt();
            int arr[][]=new int[n][3];
            int a=-1;
            int b=-1;
            for (int i = 0; i < n; i++) {
                arr[i][0]=sc.nextInt();
                arr[i][1]=sc.nextInt();
                arr[i][2]=i;
            }
            Arrays.sort(arr, new Comparator<int[]>() {
                @Override
                public int compare(int[] o1, int[] o2) {
                    if(o1[0]==o2[0])
                    return Integer.compare(o2[1],o1[1]);
                    return Integer.compare(o1[0],o2[0]);
                }
            });
//            for (int i = 0; i < n; i++) {
//                System.out.println(Arrays.toString(arr[i]));
//            }
            for (int i = 1; i <n ; i++) {

                if(arr[i][1]<=arr[i-1][1])
                {
                    a=arr[i][2]+1;
                    b=arr[i-1][2]+1;
                    break;
                }
            }
            System.out.println(a+" "+b);


    }}


    class Pair{

        int a,b;
        Pair(int a,int b)
        {
            this.a=a;
            this.b=b;
        }
    }

    class DSU
    {
        int parent[];
        int rank[];
        DSU(int n)
        {
            parent=new int[n];
            rank=new int[n];
            for (int i = 0; i < n; i++) {
                parent[i]=-1;
                rank[i]=1;
            }
        }

        int find(int s1)
        {
            if(parent[s1]==-1)
                return s1;
            return parent[s1]=find(parent[s1]);
        }

        void unite(int s1, int s2)
        {
            int p1=find(s1);
            int p2=find(s2);
            if(p1!=p2)
            {
                if(rank[p1]>rank[p2])
                {
                    parent[p2]=p1;
                    rank[p1]+=rank[p2];
                }
                else
                {
                    parent[p1]=p2;
                    rank[p2]+=rank[p1];
                }
            }
        }
    }

    class Gaph {

        HashMap<Integer, ArrayList<Integer>> hm;

        Gaph() {
            hm = new HashMap<>();
        }

        Gaph(int n) {

            hm = new HashMap<>();
            for (int i = 0; i < n; i++) {
                hm.put(i, new ArrayList<Integer>());
            }
        }

        // function for adding an edge.................................................
        public void addEdge(int a, int b, boolean isDir) {
            if (isDir) {
                if (hm.containsKey(a)) {
                    hm.get(a).add(b);
                } else {
                    hm.put(a, new ArrayList<>(Arrays.asList(b)));
                }
            } else {
                if (hm.containsKey(a)) {
                    hm.get(a).add(b);
                } else if (!hm.containsKey(a)) {
                    hm.put(a, new ArrayList<>(Arrays.asList(b)));
                }

                if (hm.containsKey(b)) {
                    hm.get(b).add(a);
                } else if (!hm.containsKey(b)) {
                    hm.put(b, new ArrayList<>(Arrays.asList(a)));
                }
            }
        }


    }

    // out.println(al.toString().replaceAll("[\\[|\\]|,]",""));