No repetition of people in the same room

Hello

I have 200 students at a secondary school who live in rooms for 2-3-4 people.
The rooms have from number 1-90 but some exceptions. Some rooms have a letter next to them, e.g. 17a.
We change rooms twice a year and would like to make sure they don't end up living with someone they've lived with the other two times??
Can they be made? so, for example, student 23 can only live with student 67 once and if it repeats, it must be shown.
They are distributed manually

Room numbers
1
3
5
6
7
8
9
10
11
12
13
14
15
15a
15b
18g
16
80
81
82
83
84
85
86
18b
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
17
17a
17b
17c
17d
69
70
71
72
73
74



Students numbers
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
17
18
19
20
21
22
23
24
25
26
28
29
30
31
32
33
34
35
36
38
39
40
41
42
43
44
45
47
49
50
51
52
53
54
55
56
57
101
103
104
105
106
107
108
109
111
112
114
115
116
117
118
119
120
121
122
124
125
126
127
128
130
131
132
133
136
137
138
139
140
141
142
143
144
145
146
147
148
150
151
152
153
154
157
158
159
161
162
163
165
166
167
168
169
170
171
173
174
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
203
205
206
207
208
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
241
242
243
244
245
246
247
249
250
251
252
253
254

on the STARTUP sheet, set the results page target. (start with Set1)
run Assign button.

Then change target to SET2
run again.

until all 3 are done.

Hello
Great job BUT....
Each room can accommodate 2, 3 or 4 students.
I have to enter the student number manually due to some restrictions

the students are distributed across all rooms.
some get 3 others not.