salesman.pas

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program salesman;
var a:array[1..40,1..40] of byte; 
    n,i,j:byte;
    min ,m :longint;
    bj:array[1..40] of boolean;
input,output:text;

procedure init;
begin
 assign(input,'salesman.in');
 reset(input);
 readln(input,n);
 for i:=1 to n do for j:=1 to n do read(input,a[i,j]);
 close(input);
 fillchar(bj,sizeof(bj),true);
 min:=99999999;
 m:=0;
end;

procedure road(step,line:byte);
var i,j,k:byte;
begin
 if step=n then
  if m+a[line,1]<min then min:=m+a[line,1] else
  else
  for i:=2 to n do
   if (i<>line) and bj[i] then
     begin
      m:=m+a[line,i]; 
      bj[line]:=false;
      if m <min then road(step+1,i); 
      m:=m-a[line,i];   bj[line]:=true; 
     end;
end;

procedure print;
begin
 assign(output,'salesman.out');
 rewrite(output);
 writeln(output,min);
 close(output);
end;

begin
 init;
 road(1,1);
 print
end.