A = {1; 2; 3; 4; 5; 6; 7}
|A| = 7
B = {3; 4; 5; 6; 7; 8}
|B| = 6
C = {5; 6; 7; 8; 9; 10; 11; 12}
|C| = 8
M = {1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12}
:)
A = {1; 2; 3; 4; 5; 6; 7}
|A| = 7
B = {3; 4; 5; 6; 7; 8}
|B| = 6
C = {5; 6; 7; 8; 9; 10; 11; 12}
|C| = 8
M = {1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12}
:)