[BZOJ1041]圆上的整点

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 #include<cstdio>
 #include<queue>
 #include<iostream>
 #include<cstring>
 #define int long long
 using namespace std;
 inline int read(){
     int ans=,f=;char chr=getchar();
     while(!isdigit(chr)){if(chr=='-') f=-;chr=getchar();}
     while(isdigit(chr)){ans=(ans<<)+(ans<<)+chr-;chr=getchar();}
     return ans*f;
 }int ans=,n,r;
 signed main() {
     r=n=read();
     if(!n) {puts("");return ;}
     while(n&^) n>>=;
     for(int i=,j;i*i<=r;++i) {
         for(j=;!(n%i);++j) n/=i;
         if(i%==) ans*=j<<|;
     }if(n>&&n%==) ans*=;
     cout<<ans*;
     return ;
 }