Given a number N, you are asked to count the number of integers between A and B inclusive which are relatively prime to N.
Two integers are said to be co-prime or relatively prime if they have no common positive divisors other than 1 or, equivalently, if their greatest common divisor is 1. The number 1 is relatively prime to every integer.
Input
The first line on input contains T (0 < T <= 100) the number of test cases, each of the next T lines contains three integers A, B, N where (1 <= A <= B <= 10 15) and (1 <=N <= 10 9).
Output
For each test case, print the number of integers between A and B inclusive which are relatively prime to N. Follow the output format below.
Sample Input
2
1 10 2
3 15 5
Sample Output
Case #1: 5
Case #2: 10
Hint
In the first test case, the five integers in range [1,10] which are relatively prime to 2 are {1,3,5,7,9}.
#include<iostream>
#include<cstdio>
#include<algorithm>
#define ll long long
#include<cstring>
#define maxn 1000005
#define ll long long
using namespace std;
ll p[maxn];
int cnt;
int t;
ll a,b,n;
void fenjie(ll x)
{
cnt=0;
for(ll i=2;i*i<=x;i++)
{
if(x%i==0)
{
p[cnt++]=i;
while(x%i==0)
x/=i;
}
}
if(x>1)
p[cnt++]=x;
}
ll solve(ll x)
{
ll sum=0,f,val;
for(int i=1;i<(1<<cnt);i++)
{
f=0,val=1;
for(int j=0;j<cnt;j++)
{
if(i&(1<<j))
{
f++;
val*=p[j];
}
}
if(f&1)
sum+=x/val;
else
sum-=x/val;
}
return x-sum;
}
int main()
{
scanf("%d",&t);
int w=0;
while(t--)
{w++;
scanf("%lld%lld%lld",&a,&b,&n);
fenjie(n);
printf("Case #%d: %lld\n",w,solve(b)-solve(a-1));
}
return 0;
}