program YesterdayDate;
var
D, M: integer;
begin
writeln('Enter the day and month of a non-leap year:');
readln(D, M);

if D = 1 then
begin
case M of
1, 3, 5, 7, 8, 10, 12: begin
D := 31;
M := M - 1;
end;
2: begin
D := 28;
M := 2;
end;
4, 6, 9, 11: begin
D := 30;
M := M - 1;
end;
end;
end
else
begin
D := D - 1;
end;

writeln('Yesterday''s date is: ', D, '.', M);
end.