LEGGIMI:
Ogni input per il problema è rappresentato da == INPUT X e le righe successive rappresentano un input valido per il programma. L'output relativo si trova nella linea succesiva a == OUTPUT X. Tutte le coppie input/output sono divise da -----. Per provare un input secondo le modalità richieste dalla traccia, si copi il contenuto relativo all'input in un file e lo si reindirizzi sullo stdin del programma creato (oppure lo si copi e incolli nel terminale e alla fine si usi CTRL+D). Gli input e gli output seguono le regole definite nella traccia del relativo appello.

ESEMPIO:
== INPUT 1 rappresenta un input e il suo contenuto parte dalla riga successiva. L'output relativo (ovvero la soluzione che dovrebbe dare il vostro programma) + la riga successiva a == OUTPUT 1.

------

== INPUT 1:
50 50 377 368
15 <> 49
21 <> 27
27 <> 34
6 <> 32
34 <> 41
3 <> 42
36 <> 39
8 <> 32
6 <> 26
4 <> 23
21 <> 29
21 <> 39
15 <> 28
33 <> 39
9 <> 23
17 <> 40
15 <> 41
26 <> 45
10 <> 20
32 <> 49
11 <> 15
17 <> 21
6 <> 15
7 <> 48
19 <> 32
14 <> 36
24 <> 28
28 <> 41
1 <> 48
2 <> 5
26 <> 50
9 <> 20
44 <> 45
17 <> 45
2 <> 36
1 <> 34
22 <> 28
16 <> 37
15 <> 46
18 <> 19
3 <> 15
10 <> 18
20 <> 32
3 <> 36
31 <> 41
7 <> 44
25 <> 46
14 <> 43
36 <> 48
2 <> 49
13 <> 15
45 <> 48
25 <> 38
22 <> 43
21 <> 44
20 <> 41
21 <> 28
5 <> 6
14 <> 39
18 <> 23
31 <> 36
24 <> 48
29 <> 35
1 <> 43
37 <> 49
8 <> 22
4 <> 15
12 <> 33
26 <> 49
5 <> 44
5 <> 12
17 <> 23
46 <> 49
21 <> 50
30 <> 36
34 <> 43
3 <> 17
8 <> 31
38 <> 47
26 <> 47
47 <> 48
3 <> 22
23 <> 35
20 <> 48
20 <> 40
15 <> 16
3 <> 32
22 <> 46
27 <> 50
18 <> 31
3 <> 37
6 <> 22
8 <> 34
20 <> 28
7 <> 23
36 <> 47
3 <> 39
35 <> 36
14 <> 32
27 <> 29
13 <> 25
21 <> 40
14 <> 41
13 <> 37
8 <> 17
24 <> 40
25 <> 40
14 <> 49
2 <> 43
15 <> 37
9 <> 33
12 <> 32
16 <> 26
25 <> 33
5 <> 26
17 <> 49
13 <> 31
2 <> 21
28 <> 45
24 <> 43
39 <> 50
9 <> 34
16 <> 33
26 <> 34
9 <> 46
6 <> 20
43 <> 46
6 <> 39
11 <> 21
1 <> 27
37 <> 44
30 <> 35
18 <> 43
4 <> 6
10 <> 12
30 <> 38
30 <> 32
36 <> 50
31 <> 39
28 <> 39
11 <> 47
38 <> 48
4 <> 30
7 <> 32
6 <> 49
27 <> 41
15 <> 21
1 <> 47
19 <> 46
5 <> 11
1 <> 20
25 <> 41
27 <> 46
13 <> 20
7 <> 17
19 <> 42
13 <> 14
4 <> 34
22 <> 38
36 <> 45
23 <> 46
6 <> 17
36 <> 41
3 <> 9
1 <> 19
35 <> 50
33 <> 45
35 <> 37
1 <> 35
13 <> 26
22 <> 35
35 <> 42
14 <> 46
24 <> 49
28 <> 33
7 <> 22
12 <> 21
13 <> 32
5 <> 33
13 <> 43
8 <> 43
14 <> 22
5 <> 43
21 <> 23
19 <> 33
8 <> 38
31 <> 34
20 <> 25
5 <> 17
11 <> 28
6 <> 31
4 <> 25
34 <> 47
12 <> 37
6 <> 21
12 <> 44
5 <> 35
34 <> 46
16 <> 45
37 <> 45
19 <> 35
21 <> 32
16 <> 27
1 <> 26
1 <> 11
18 <> 37
2 <> 14
24 <> 31
27 <> 49
1 <> 14
12 <> 25
5 <> 50
24 <> 44
21 <> 35
20 <> 43
14 <> 24
25 <> 43
22 <> 41
12 <> 34
3 <> 34
10 <> 44
18 <> 45
7 <> 42
2 <> 13
24 <> 26
31 <> 48
38 <> 39
5 <> 23
3 <> 19
16 <> 18
5 <> 19
24 <> 41
29 <> 36
29 <> 46
6 <> 11
4 <> 20
19 <> 50
34 <> 48
16 <> 29
38 <> 44
40 <> 42
29 <> 32
28 <> 50
3 <> 29
24 <> 36
19 <> 23
2 <> 8
4 <> 48
9 <> 25
27 <> 44
15 <> 34
15 <> 47
1 <> 16
44 <> 46
17 <> 35
27 <> 43
8 <> 44
30 <> 48
34 <> 36
5 <> 38
16 <> 25
1 <> 30
34 <> 40
7 <> 47
28 <> 31
36 <> 37
12 <> 36
1 <> 38
2 <> 24
14 <> 44
20 <> 30
3 <> 6
27 <> 40
41 <> 44
7 <> 14
10 <> 41
9 <> 19
1 <> 24
14 <> 45
6 <> 45
14 <> 29
12 <> 29
11 <> 26
21 <> 43
1 <> 33
8 <> 27
2 <> 45
19 <> 36
18 <> 33
23 <> 33
31 <> 37
43 <> 45
17 <> 19
10 <> 23
22 <> 50
4 <> 8
5 <> 30
5 <> 21
3 <> 25
8 <> 9
25 <> 48
23 <> 40
42 <> 50
21 <> 34
11 <> 24
23 <> 45
22 <> 45
22 <> 40
9 <> 49
6 <> 8
4 <> 40
18 <> 25
35 <> 47
41 <> 48
37 <> 41
2 <> 26
6 <> 48
25 <> 32
7 <> 8
9 <> 28
10 <> 32
10 <> 24
2 <> 34
1 <> 37
19 <> 45
21 <> 31
11 <> 29
15 <> 26
13 <> 48
12 <> 41
7 <> 26
18 <> 20
2 <> 18
4 <> 28
39 <> 48
4 <> 7
39 <> 42
5 <> 36
6 <> 42
3 <> 10
7 <> 28
11 <> 13
7 <> 33
16 <> 34
13 <> 44
2 <> 29
43 <> 50
18 <> 29
10 <> 31
18 <> 27
12 <> 22
9 <> 36
6 <> 50
18 <> 50
38 <> 45
4 <> 32
8 <> 29
33 <> 44
13 <> 18
28 <> 43
21 <> 46
6 <> 9
21 <> 41
23 <> 30
5 <> 47
2 <> 6
29 <> 42
4 <> 17
7 <> 37
1 <> 22
29 <> 34
7 <> 41
29 <> 33
27 <> 33
11 <> 38
22 <> 48
40 <> 44
9 <> 20
15 <> 47
36 <> 41
1 <> 46
2 <> 4
2 <> 19
33 <> 47
16 <> 46
31 <> 43
1 <> 28
47 <> 50
3 <> 50
3 <> 32
39 <> 48
14 <> 35
10 <> 16
16 <> 48
20 <> 41
19 <> 34
15 <> 19
3 <> 14
21 <> 26
8 <> 33
37 <> 47
25 <> 49
27 <> 45
4 <> 31
16 <> 42
15 <> 31
11 <> 34
5 <> 9
2 <> 27
29 <> 39
2 <> 11
15 <> 38
38 <> 46
34 <> 47
5 <> 13
27 <> 38
46 <> 47
28 <> 30
4 <> 23
9 <> 42
20 <> 44
12 <> 36
16 <> 29
3 <> 16
19 <> 43
42 <> 46
5 <> 24
13 <> 15
15 <> 21
5 <> 15
24 <> 39
9 <> 14
7 <> 29
10 <> 36
3 <> 29
30 <> 48
18 <> 25
18 <> 20
8 <> 21
25 <> 46
19 <> 48
20 <> 43
27 <> 30
15 <> 41
30 <> 42
21 <> 37
1 <> 25
32 <> 36
14 <> 20
22 <> 36
1 <> 24
26 <> 43
13 <> 21
38 <> 41
2 <> 45
31 <> 38
29 <> 49
1 <> 23
24 <> 36
6 <> 34
35 <> 50
35 <> 44
5 <> 45
4 <> 47
21 <> 38
8 <> 18
16 <> 39
7 <> 17
22 <> 24
23 <> 33
3 <> 20
17 <> 31
25 <> 47
3 <> 10
36 <> 39
47 <> 49
33 <> 41
19 <> 31
11 <> 46
5 <> 44
31 <> 40
9 <> 41
39 <> 46
19 <> 42
14 <> 24
7 <> 23
24 <> 44
11 <> 29
11 <> 43
13 <> 26
18 <> 36
7 <> 20
38 <> 43
17 <> 45
8 <> 40
27 <> 37
5 <> 32
30 <> 35
7 <> 14
8 <> 32
9 <> 36
7 <> 8
16 <> 49
6 <> 42
5 <> 30
13 <> 34
9 <> 15
7 <> 27
6 <> 30
37 <> 40
40 <> 48
15 <> 26
5 <> 35
9 <> 30
19 <> 35
11 <> 23
38 <> 42
26 <> 41
9 <> 16
1 <> 49
13 <> 25
2 <> 47
24 <> 38
24 <> 33
10 <> 15
42 <> 50
11 <> 38
19 <> 25
29 <> 34
26 <> 31
16 <> 23
29 <> 50
33 <> 49
19 <> 23
5 <> 25
29 <> 32
5 <> 23
20 <> 24
22 <> 33
20 <> 49
19 <> 30
10 <> 19
19 <> 44
8 <> 30
10 <> 22
10 <> 47
19 <> 45
15 <> 25
4 <> 37
31 <> 46
3 <> 47
13 <> 43
12 <> 30
7 <> 13
6 <> 11
12 <> 28
36 <> 38
7 <> 30
34 <> 42
31 <> 39
14 <> 49
17 <> 28
32 <> 50
16 <> 41
17 <> 48
7 <> 31
1 <> 6
10 <> 12
1 <> 50
11 <> 35
17 <> 37
18 <> 30
22 <> 48
32 <> 48
10 <> 18
16 <> 20
22 <> 27
3 <> 45
25 <> 31
36 <> 43
9 <> 11
6 <> 37
20 <> 28
1 <> 33
14 <> 40
14 <> 18
3 <> 38
8 <> 13
15 <> 48
34 <> 49
20 <> 37
4 <> 18
8 <> 11
12 <> 24
3 <> 37
20 <> 26
10 <> 31
4 <> 38
15 <> 29
8 <> 38
19 <> 50
8 <> 31
16 <> 50
8 <> 47
11 <> 36
8 <> 29
5 <> 18
4 <> 17
3 <> 44
40 <> 41
35 <> 36
16 <> 45
10 <> 24
34 <> 48
25 <> 50
12 <> 48
7 <> 10
40 <> 49
23 <> 31
13 <> 31
9 <> 13
18 <> 37
2 <> 39
1 <> 45
7 <> 42
23 <> 43
18 <> 35
17 <> 41
7 <> 44
11 <> 47
17 <> 33
15 <> 28
5 <> 31
32 <> 43
3 <> 24
22 <> 32
11 <> 26
22 <> 30
41 <> 50
13 <> 47
13 <> 38
9 <> 49
10 <> 40
11 <> 28
19 <> 22
14 <> 45
15 <> 37
16 <> 43
7 <> 48
2 <> 6
3 <> 9
16 <> 22
27 <> 49
7 <> 21
13 <> 33
5 <> 26
6 <> 45
7 <> 39
16 <> 35
32 <> 35
40 <> 45
22 <> 43
15 <> 27
41 <> 49
2 <> 15
35 <> 43
6 <> 20
38 <> 45
1 <> 2
5 <> 22
1 <> 5
12 <> 15
27 <> 33
8 <> 49
27 <> 41
4 <> 44
8 <> 16
22 <> 25
35 <> 41
18 <> 26
21 <> 40
4 <> 50
9 <> 33
29 <> 40
37 <> 39
41 <> 46
15 <> 43
6 <> 47
4 <> 15
17 <> 32
3 <> 4
3 <> 34
18 <> 32
5 <> 37
14 <> 50
19 <> 38
38 <> 44
23 <> 41
17 <> 43
35 <> 42
7 <> 35
34 <> 37
28 <> 34
15 <> 44
2 <> 33
34 <> 40
22 <> 31
7 <> 43
24 <> 30
14 <> 30
23 <> 49
3 <> 18
12 <> 21
17 <> 44
4 <> 46
31 <> 32
47 <> 48
16 <> 44
10 <> 23
18 <> 38
21 <> 27
42 <> 44
10 <> 30
29 <> 37
20 <> 27
43 <> 49
9 <> 50
8 <> 12
41 <> 43
29 <> 30
35 <> 45
14 <> 48
25 <> 43
4 <> 25
36 <> 44
2 <> 20
12 <> 31
15 <> 45
43 <> 45
35 <> 46
22 <> 37
4 <> 8
33 <> 36
7 <> 16
25 <> 44


== OUTPUT 1:
NO

------

== INPUT 2:
12 12 16 16
1 <> 2
1 <> 3
3 <> 4
2 <> 4
4 <> 5
5 <> 6
6 <> 7
7 <> 8
8 <> 5
5 <> 7
6 <> 8
6 <> 12
12 <> 9
9 <> 10
10 <> 11
11 <> 12
12 <> 8
11 <> 12
10 <> 8
11 <> 10
12 <> 10
11 <> 8
10 <> 6
9 <> 6
6 <> 4
7 <> 4
7 <> 9
4 <> 5
3 <> 2
3 <> 5
2 <> 1
1 <> 5

== OUTPUT 2:
NO

------

== INPUT 3:
12 12 16 16
1 <> 2
1 <> 3
3 <> 4
2 <> 4
4 <> 5
5 <> 6
6 <> 7
7 <> 8
8 <> 5
5 <> 7
6 <> 8
6 <> 12
12 <> 9
9 <> 10
10 <> 11
11 <> 12
3 <> 5
3 <> 8
5 <> 6
6 <> 8
6 <> 7
7 <> 1
1 <> 12
11 <> 12
11 <> 7
1 <> 11
7 <> 12
11 <> 4
4 <> 2
9 <> 4
9 <> 10
10 <> 2

== OUTPUT 3:
SI