pku3461 Oulipo

对于每一组数据(b,a)，统计b在a中出现的次数。

一道裸的KMP匹配题，你用BM我也没意见。

program pku3461(input,output);
var
   a,b      : ansistring;
   next      : array[0..20000] of longint;
   cases  : longint;
   i,j,k  : longint;
   answer : longint;
begin
   readln(cases);
   for k:=1 to cases do
   begin
      readln(b);
      readln(a);
      fillchar(next,sizeof(next),0);
      j:=0;
      next[1]:=0;
      for i:=2 to length(b) do
      begin
     while (b[j+1]<>b[i])and(j>0) do
        j:=next[j];
     if b[j+1]=b[i] then
        inc(j);
     next[i]:=j;
      end;
      j:=0;
      answer:=0;
      for i:=1 to length(a) do
      begin
     while (j>0)and(a[i]<>b[j+1]) do
        j:=next[j];
     if a[i]=b[j+1] then
        inc(j);
     if j=length(b) then
     begin
        inc(answer);
        j:=next[j];
     end;
      end;
      writeln(answer);
   end;
end.