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Cod sursa(job #181425)
Program dijkstra;
const inf = 50000000;
type pnod = ^nod;
nod = record
nod : word;
cost : longint;
urm : pnod;
end;
var A,u : array [1..50010] of pnod;
urm : pnod;
H : array [1..50010] of pnod;
D : array [1..50010] of longint;
n,x,y,c,lvl : word;
i,m : longint;
f,g : text;
procedure shift(n,x:word);
var son : word;
c : pnod;
begin
repeat
son := 0;
if 2*x<=n then begin
if 2*x+1<=n then if H[2*x]^.cost>H[2*x+1]^.cost then son := 2*x+1
else son := 2*x
else son := 2*x;
if H[son]>H[x] then son := 0;
end;
if son<>0 then begin
c := H[son];
H[son] := H[x];
H[x] := c;
x := son;
end;
until son=0;
end;
procedure percolate(x:word);
var c : pnod;
begin
if x>1 then
if H[x]^.cost<H[x div 2]^.cost then begin
c := H[x];
H[x] := H[x div 2];
H[x div 2] := c;
percolate(x div 2);
end;
end;
procedure delete;
begin
H[1] := H[lvl];
dec(lvl);
shift(lvl,1);
end;
procedure add(x:pnod);
begin
lvl := lvl+1;
H[lvl] := x;
percolate(lvl);
end;
procedure dijkstra;
var k : word;
begin
while lvl<>0 do begin
k := H[1]^.nod;
delete;
urm := A[k];
while urm<>nil do begin
if D[urm^.nod]>D[k]+urm^.cost then begin
D[urm^.nod] := D[k]+urm^.cost;
add(urm);
end;
urm := urm^.urm;
end;
end;
end;
begin
assign(f,'dijkstra.in');
reset(f);
assign(g,'dijkstra.out');
rewrite(g);
readln(f,n,m);
for i := 1 to n do begin
A[i] := nil;
D[i] := inf;
end;
for i := 1 to m do begin
readln(f,x,y,c);
if A[x]=nil then begin
new(A[x]);
A[x]^.nod := y;
A[x]^.cost := c;
A[x]^.urm := nil;
u[x] := A[x];
end
else begin
new(urm);
urm^.nod := y;
urm^.cost := c;
urm^.urm := nil;
u[x]^.urm := urm;
u[x] := urm;
end;
end;
lvl := 0;
urm := A[1];
while urm<>nil do begin
inc(lvl);
H[lvl] := urm;
D[urm^.nod] := urm^.cost;
urm := urm^.urm;
end;
for i := lvl div 2 downto 1 do
shift(lvl,i);
dijkstra;
for i := 2 to n do
if D[i]<>inf then write(g,D[i],' ')
else write(g,'0 ');
close(f);
close(g);
end.