CSU七月校赛A

 /*#include <iostream>
 #include<cstdio>
 #include<algorithm>
 #include<cstring>
 using namespace std;

 int main()
 {
 long long n;
 int a[100];
 int t;
 long long cnt;
 while(~scanf("%lld",&n))
 {
 cnt=0;
 memset(a,0,sizeof(a));
 for(int i=1;i<=n;i++)
 {
 //a[1]=
 for(int t=1;t<=n;t++)
 {
 if(t%i==0)
 a[t]=!a[t];

 }
 }
 for(int i=1;i<=n;i++)
 {
 if(a[i]==1)
 cnt++;
 }

 printf("%lld\n",cnt);
 }
 return 0;
 }
 */
 #include <iostream>
 #include<cstdio>
 #include<algorithm>
 #include<cstring>
 #include<cmath>
 using namespace std;
 typedef long long ll;
 int main()
 {
 ll n;
 while(~scanf("%lld",&n))
 {
 printf("%d\n",(int)sqrt(n));
 }
 return ;
 }
 /*
 #include <iostream>
 #include<cstdio>
 #include<algorithm>
 #include<cstring>
 using namespace std;
 typedef long long ll;
 int main()
 {
 ll n;
 ll cnt;
 while(~scanf("%lld",&n))
 {
 cnt=0;
 for(ll i=1;i<=n/2;i++)
 {
 if(n%i==0)
 cnt++;
 }
 printf("%lld\n",cnt);

 }
 return 0;
 }
 */