program ti1029;
var
  f:array[0..501,0..501]of integer;
  w,dp:array[0..501,0..501]of extended;
  i,j,k,n,m:integer;

procedure print(x,y:integer);
  begin
    if x<>1
      then begin
             if f[x,y]=y
               then print(x-1,y)
               else print(x,f[x,y]);
           end;
    writeln(y);
  end;

begin
  readln(m,n);
  for i:=1 to m do
   for j:=1 to n do
     read(w[i,j]);
  fillchar(dp,sizeof(dp),0);
  fillchar(f,sizeof(f),0);
  for i:=1 to n do
    dp[1][i]:=w[1][i];
  for i:=2 to m do
    begin
      for j:=1 to n do
        begin
          dp[i][j]:=dp[i-1][j]+w[i][j];
          f[i][j]:=j;
        end;
      for j:=2 to n do
        if dp[i][j-1]+w[i][j]<dp[i][j]
          then begin
                 dp[i][j]:=dp[i][j-1]+w[i][j];
                 f[i][j]:=j-1;
               end;
      for j:=n-1 downto 1 do
        if dp[i][j+1]+w[i][j]<dp[i][j]
          then begin
                 dp[i][j]:=dp[i][j+1]+w[i][j];
                 f[i][j]:=j+1;
               end;
    end;
  j:=1;
  for i:=1 to n do
    if dp[m][i]<dp[m][j]
      then j:=i;
  print(m,j);
end.

try

5 6
525   0 171   0 872 673
  0 843   0   0   0   0
  0 277   0 202   0   0
  0   0 733 957  65  96
637 566   0   0   0 441

answer:
4 4 5 5 5 5

Well, accepted got now.
For those who use the method of calculating the intersection of three circles, pay attention that there might be a circle inside another or internal tangent to another.

Where you see in this task any optimal substructure (typical fo dp)?

the problem seems to be very easy but idk, i have WA#4 too

Same for me, fails at 4. Please double check.

A[1] := 0;
A[2] := 1; // this line is wrong, must be A[2] := 1 mod P

test
1 1
answer is 0

thX AC

NO
"Meanwhile, the wall of fire continued to approach the cart. Time was running out, and a plan had to be developed fast. WIZARDS CAN TURN TO A SIDE TUNNEL ONLY ONCE BECAUSE THE CART IS VERY OLD AND NOT SUITED WELL FOR MAKING TURNS. But which tunnel to use?"

Edited by author 21.10.2012 12:13

Edited by author 21.10.2012 03:11

I corrected my mistake!!! sorry for all ;) got AC! I had Crash 1!!! and solve in Java and found my mistake!!!

1. "?" means that there were no accepted submissions for this problem in first 4 hours and there were some submissions in the last hour. So results are effectively frozen at 4:00 mark.

2. Longest and biggest.

Yes please!   Hopefully very soon!