BZOJ_P1503&Codevs_P2912 [HAOI2007]反素数ant(打表+DFS)

BZOJ传送门 Codevs传送门

Time Limit: 10 Sec Memory Limit: 162 MB

Submit: 2428 Solved: 1351

[Submit][Status][Discuss]

Description

对于任何正整数x，其约数的个数记作g(x)。例如g(1)=1、g(6)=4。

如果某个正整数x满足：g(x)>g(i) 0

#include <cstdio>
int a[]={1396755360,1102701600,735134400,698377680,551350800,367567200,294053760,245044800,183783600,147026880,122522400,110270160,73513440,61261200,43243200,36756720,32432400,21621600,17297280,14414400,10810800,8648640,7207200,6486480,4324320,3603600,2882880,2162160,1441440,1081080,720720,665280,554400,498960,332640,277200,221760,166320,110880,83160,55440,50400,45360,27720,25200,20160,15120,10080,7560,5040,2520,1680,1260,840,720,360,240,180,120,60,48,36,24,12,6,4,2,1,0};
int main(){
int n;scanf("%lld",&n);
for(int i=0;;i++) if(a[i]<=n){printf("%d",a[i]);break;}
return 0;
}