hdu 2512 反素数 水题

水题，从1到5000打表即可。

传送门：http://acm.hdu.edu.cn/showproblem.php?pid=2521

#include <cmath>#include <cstdio>#include <cstring>#include <cstdlib>#include <iostream>#include <algorithm>using namespace std;int f[5005];void Pre_Deal() {for(int i = 1 ; i <= 5000 ; i ++) {for(int j = 1 ; j <= sqrt(i) ; j ++) {if(i % j == 0) f[i] += 2;}int ff = sqrt(i);if(ff * ff == i) f[i] --;//ff应该为整数。}}void Deal_with() {int T;Pre_Deal();scanf("%d",&T);while(T--) {int a1,a2;scanf("%d %d",&a1,&a2);int maxnum = f[a1],flag = 0;for(int i = a1 + 1; i <= a2 ; i ++) {maxnum = max(maxnum , f[i]);}for(int i = a1 ; i <= a2 ; i++) {if(f[i] == maxnum){printf("%d\n",i);break;}}}}int main(void) {//freopen("a.in","r",stdin);Deal_with();return 0;}