POJ 1837(Dp水题）

这题居然不用高精度就能过……测试数据好弱

Program P1837;var   c,g,i,j,k,p:longint;   li,w:array[1..20] of longint;   f:array[1..20,-7500..7500] of longint;begin   fillchar(f,sizeof(f),0);   read(c,g);   for i:=1 to c do read(li[i]);   for i:=1 to g do read(w[i]);   for i:=1 to c do f[1,li[i]*w[1]]:=1;   for i:=2 to g do      for j:=1 to c do      begin         p:=li[j]*w[i];         if p<0 then         begin            for k:=-7500 to 7500+p do               if f[i-1,k-p]>0 then                  inc(f[i,k],f[i-1,k-p])         end         else         begin            for k:=-7500+p to 7500 do               if f[i-1,k-p]>0 then                  inc(f[i,k],f[i-1,k-p]);         end;      end;   writeln(f[g,0]);end.