Cod sursa(job #266900)

Utilizator TecoVacaretu Daniel Teco Data 26 februarie 2009 11:51:53
Problema Distante Scor 0
Compilator fpc Status done
Runda Arhiva de probleme Marime 1.32 kb
type muchie=record
            x,y,cost:longint;
            end;
const q=2000000000;
var v:array[1..50001]of muchie;
    d,tz:array[1..100001]of longint;
    f,g:text;
    t:byte;
    n,poz,pozz,xp,z,m,i,s:longint;
    modif:boolean;

procedure init;
begin
for i:=1 to m do begin
    read(f,poz,pozz,s);
    v[i].x:=poz;
    v[i].y:=pozz;
    v[i].cost:=s;
    if poz=xp then d[pozz]:=s;
end;
for i:=1 to n do if (d[i]=0) and (i<>xp) then d[i]:=q;
end;

procedure bellford;
begin
repeat
modif:=false;
for i:=1 to m do begin
          s:=d[v[i].x]+v[i].cost;
          poz:=v[i].y;
          if s<d[poz] then begin
                           d[poz]:=s;
                           modif:=true;
                           end;
          end;
until not modif;
end;

function verif:boolean;
var ok:boolean;
begin
ok:=true;
for i:=1 to n do if d[i]<>tz[i] then begin
                                     ok:=false;
                                     break;
                                     end;
verif:=ok;
end;

begin
assign(f,'distante.in');reset(f);
assign(g,'distante.out');rewrite(g);
read(f,t);
for z:=1 to t do begin
    read(f,n,m,xp);
    for i:=1 to n do read(f,tz[i]);
    init;
    bellford;
    if verif then writeln(g,'DA')
             else writeln(g,'NU');
end;
close(g);
end.