51NOD1277 字符串中的最大值

题目链接：传送门
kmp裸题
因为前缀是从长到短覆盖的，所以从长到短累计加和
贴代码

 var s:ansistring;     n,i,j:longint;     a:array[0..100005]of char;     f,p:array[0..100005]of longint;     ans:int64; begin//  assign(input,'1277.in');reset(input);//  assign(output,'1277.out');rewrite(output);  readln(s);  n:=length(s);  for i:=1 to n do a[i]:=s[i];  fillchar(p,sizeof(p),0);  j:=0;  for i:=2 to n do   begin    while (j>0)and(a[j+1]<>a[i]) do j:=p[j];    if a[j+1]=a[i] then inc(j);    p[i]:=j;   end;  ans:=0;  fillchar(f,sizeof(f),0);  for i:=n downto 1 do   begin    inc(f[i]);    inc(f[p[i]],f[i]);   end;  for i:=1 to n do   if int64(i)*int64(f[i])>ans then ans:=int64(i)*int64(f[i]);  writeln(ans);//  close(input);close(output); end.

【写的有漏洞的，欢迎路过大神吐槽】
2017/09/06 22:58:56
Ending.