bzoj1053: [HAOI2007]反素数ant

传送门
打表大法好，毕竟数据范围小。
正解：爆搜+强力剪枝（见这里，可以过加强版）

const a:array [1..68] of longint=(1,2,4,6,12,24,36,48,60,120,180,240,360,720,840,1260,1680,2520,5040,7560,10080,15120,20160,25200,27720,45360,50400,55440,83160,110880,166320,221760,277200,332640,498960,554400,665280,720720,1081080,1441440,2162160,2882880,3603600,4324320,6486480,7207200,8648640,10810800,14414400,17297280,21621600,32432400,36756720,43243200,61261200,73513440,110270160,122522400,147026880,183783600,245044800,294053760,367567200,551350800,698377680,735134400,1102701600,1396755360);var  i,n:longint;begin  read(n);  for i:=68 downto 1 do if (a[i]<=n) then break;  write(a[i]);end.