2748: [HAOI2012]音量调节

 2    i,j,k,l,m,n,a1,a2,a3,a4:longint;
 3    a:array[0..100,0..2000] of longint;
 4 begin
 5      readln(n,l,m);
 6      fillchar(a,sizeof(a),0);
 7      a[0,l]:=1;
 8      for i:=1 to n do
 9          begin
10               k:=0;
11               read(a1);
12               for j:=0 to m do
13                   begin
14                        if (j+a1)<=m then
15                           begin
16                                if a[i-1,j+a1]=1 then
17                                   begin
18                                        a[i,j]:=1;
19                                        k:=1;
20                                   end;
21                           end;
22                        if (j-a1)>=0 then
23                           begin
24                                if a[i-1,j-a1]=1 then
25                                   begin
26                                        a[i,j]:=1;
27                                        k:=1;
28                                   end;
29                           end;
30                   end;
31               if k=0 then
32                  begin
33                       writeln(-1);
34                       halt;
35                  end;
36          end;
37      for i:=m downto 0 do
38          if a[n,i]=1 then
39             begin
40                  writeln(i);
41                  halt;
42             end;
43 end.