学步园

见《数学与程序设计》P255

program poj3440;
var
  p,q,m,n,i,j,k:longint;
  squ,s,c,t:extended;
begin
  read(p);
  for q:=1 to p do
    begin
      writeln('Case ',q,':');
      read(n,m,t,c);
      c:=c/2;
      squ:=n*t*m*t;
      s:=(t-c)*(t-c)*4+(t-2*c)*(t-c)*2*(n+m-4)+(t-2*c)*(t-2*c)*(n-2)*(m-2);
      writeln('Probability of covering 1 tile  = ',s/squ*100:0:4,'%');
      s:=(t-2*c)*(2*c)*((n-1)*(m-2)+(m-1)*(n-2))+(t-c)*(2*c)*2*(n+m-2);
      writeln('Probability of covering 2 tiles = ',s/squ*100:0:4,'%');
      s:=((2*c)*(2*c)-pi*c*c)*(n-1)*(m-1);
      writeln('Probability of covering 3 tiles = ',s/squ*100:0:4,'%');
      s:=pi*c*c*(n-1)*(m-1);
      writeln('Probability of covering 4 tiles = ',s/squ*100:0:4,'%');
      writeln;
    end;
end.