24
9 83
90 31
83 3
83 3
21 31
83 3
32 31
12 21
31 21
90 32
32 21
12 9
12 31
9 83
83 12
32 3
32 83
90 31
9 32
31 21
83 90
32 21
21 3
32 9
 25
91 57
2 73
54 57
2 57
23 57
2 6
57 54
57 23
91 54
91 23
57 23
91 57
54 2
6 91
57 54
2 57
57 91
73 91
57 23
91 57
2 73
91 2
23 6
2 73
23 6
 29
8 18
33 75
69 22
97 95
1 97
78 10
88 18
13 3
19 64
98 12
79 92
41 72
69 15
98 31
57 74
15 56
36 37
15 66
63 100
16 42
47 56
6 4
73 15
30 24
27 71
12 19
88 69
85 6
50 11
 30
67 21
85 39
85 87
21 39
66 85
10 95
10 21
87 85
82 21
67 21
95 10
21 39
82 21
21 66
66 39
95 30
67 85
66 82
85 82
21 66
10 39
67 10
21 85
10 82
85 95
10 85
21 39
85 39
39 10
95 67
 22
78 92
15 92
92 78
78 80
92 16
24 80
92 16
16 92
78 16
24 78
80 78
92 80
16 80
80 78
15 78
92 16
24 15
24 80
80 16
16 80
92 80
24 80
 29
80 27
69 80
27 80
69 80
80 27
80 27
80 27
80 69
27 69
80 69
80 27
27 69
69 27
80 69
27 69
69 80
27 69
80 69
80 27
69 27
27 69
27 80
80 27
69 80
27 69
80 69
69 80
69 80
27 80
 4
8 7
8 7
7 8
7 8
 30
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
1 2
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
2 1
 29
78 27
50 68
24 26
68 43
38 78
26 38
78 28
28 26
27 24
23 38
24 26
24 43
61 50
38 78
27 23
61 26
27 28
43 23
28 78
43 27
43 78
27 61
28 38
61 78
50 26
43 27
26 78
28 50
43 78
 10
68 42
1 35
25 70
59 79
65 63
46 6
28 82
92 62
43 96
37 28
 15
2 1
1 2
1 2
1 2
2 1
2 1
2 1
1 2
2 1
2 1
2 1
1 2
2 1
2 1
1 2
 30
100 99
58 59
56 57
54 55
52 53
50 51
48 49
46 47
44 45
42 43
40 41
38 39
36 37
34 35
32 33
30 31
28 29
26 27
24 25
22 23
20 21
18 19
16 17
14 15
12 13
10 11
8 9
6 7
4 5
2 3
 13
76 58
32 85
99 79
23 58
96 59
72 35
53 43
96 55
41 78
75 10
28 11
72 7
52 73
 12
1 2
1 2
1 2
1 2
1 2
1 2
2 1
2 1
2 1
2 1
2 1
2 1
 6
1 2
1 2
1 2
1 2
1 2
2 1
 30
19 71
7 89
89 71
21 7
19 21
7 89
19 71
89 8
89 21
19 8
21 7
8 89
19 89
7 21
19 8
19 7
7 19
8 21
71 21
71 89
7 19
7 19
21 7
21 19
21 19
71 8
21 8
71 19
19 71
8 21
 15
9 3
2 6
7 6
5 10
9 5
8 1
10 5
2 8
4 5
9 8
5 3
3 8
9 8
4 10
8 5
 30
10 39
89 1
78 58
75 99
36 13
77 50
6 97
79 28
27 52
56 5
93 96
40 21
33 74
26 37
53 59
98 56
61 65
42 57
9 7
25 63
74 34
96 84
95 47
12 23
34 21
71 6
27 13
15 47
64 14
12 77
 28
31 66
31 91
91 31
97 66
31 66
31 66
66 91
91 31
97 31
91 97
97 31
66 31
66 97
91 31
31 66
31 66
66 31
31 97
66 97
97 31
31 91
66 91
91 66
31 66
91 66
66 31
66 31
91 97
 30
46 100
87 53
34 84
44 66
23 20
50 34
90 66
17 39
13 22
94 33
92 46
63 78
26 48
44 61
3 19
41 84
62 31
65 89
23 28
58 57
19 85
26 60
75 66
69 67
76 15
64 15
36 72
90 89
42 69
45 35
 30
44 17
44 17
44 17
17 44
44 17
44 17
17 44
17 44
17 44
44 17
44 17
44 17
44 17
44 17
17 44
17 44
17 44
44 17
44 17
17 44
44 17
44 17
44 17
17 44
17 44
44 17
17 44
44 17
44 17
44 17
 2
46 6
6 46
 4
1 2
1 2
2 1
2 1
 18
6 90
100 79
26 100
67 100
29 100
100 32
94 88
18 58
59 65
51 56
64 68
34 2
6 98
95 82
34 2
40 98
83 78
29 100
 18
6 90
70 79
26 52
67 81
29 95
41 32
94 88
18 58
59 65
51 56
64 68
34 2
6 98
95 82
34 2
40 98
83 78
29 2
 23
43 78
31 28
58 80
66 63
20 4
51 95
40 20
50 14
5 34
36 39
77 42
64 97
62 89
16 56
8 34
58 16
37 35
37 66
8 54
50 36
24 8
68 48
85 33
 25
2 1
1 2
1 2
1 2
2 1
1 2
1 2
1 2
2 1
2 1
2 1
1 2
1 2
1 2
2 1
2 1
2 1
1 2
2 1
1 2
2 1
2 1
2 1
2 1
1 2
 7
4 7
52 55
16 4
55 4
20 99
3 4
7 52

59
 96
 10
 100
 74
 277
 8
 450
 73
 1
 108
 0
 0
 72
 10
 154
 20
 6
 210
 4
 418
 2
 8
 8
 1
 6
 312
 6

//package Round_164;

import java.util.*;
import java.io.*;

import static java.lang.Math.*;

public class a {

    int a[][];
    int n;
    
    void r(){
        int ans = 0;
        for (int i = 0; i<n; i++)
            for (int j = 0; j<n; j++){
                if (i == j) continue;
                if (a[i][0] == a[j][1]) ans++;
            }
        
        out.println(ans);

    }
    
    void solve() throws Exception {
        n = in.nextInt();
        a = new int[n][2];
        for (int i = 0; i<n; i++){
            a[i][0] =in.nextInt();
            a[i][1] = in.nextInt();
        }
                
        
        
        
        
        

    }

    FastScanner in;
    PrintWriter out;

    String input = "";
    String output = "";

    void run() {
        try {
            if (input.length() > 0) {
                in = new FastScanner(new BufferedReader(new FileReader(input)));
            } else
                in = new FastScanner(new BufferedReader(new InputStreamReader(
                        System.in)));
            if (output.length() > 0)
                out = new PrintWriter(new FileWriter(output));
            else
                out = new PrintWriter(System.out);

            solve();

            out.flush();
            out.close();
        } catch (Exception ex) {
            ex.printStackTrace();
            out.flush();
            out.close();
        } finally {
            out.close();
        }
    }

    public static void main(String[] args) {
        new a().run();
    }

    class FastScanner {
        BufferedReader bf;
        StringTokenizer st;

        public FastScanner(BufferedReader bf) {
            this.bf = bf;
        }

        public String next() throws IOException {
            while (st == null || !st.hasMoreTokens())
                st = new StringTokenizer(bf.readLine());
            return st.nextToken();
        }

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

        public String nextLine() throws IOException {
            return bf.readLine();
        }

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

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

    }

}
