rt
int aaa(int n)
{
int ret=1,i;
for(i=2;i*i<=n;i++){
if(n%i==0)
{
n/=i,ret*=i-1;
while(n%i==0)
n/=i,ret*=i;
}
}
if(n>1)
ret*=n-1;
return ret;
rt
int aaa(int n)
{
int ret=1,i;
for(i=2;i*i<=n;i++){
if(n%i==0)
{
n/=i,ret*=i-1;
while(n%i==0)
n/=i,ret*=i;
}
}
if(n>1)
ret*=n-1;
return ret;