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- #include<bits/stdc++.h>
- using namespace std;
- #define x 10000000
- bool mark[x+5]={false};
- vector<int>isprime;
- void sieve()
- {
- int i,j,k=0;
- mark[0]=true;
- mark[1]=true;
- for(i=2;i*i<=x;i++)
- {
- if(mark[i]==false)
- {
- for(j=i*i;j<=x;j+=i)
- mark[j]=true;
- }
- }
- for(i=2;i<=x;i++){
- if(mark[i]==false){
- isprime.push_back(i);
- }
- }
- }
- int main()
- {
- sieve();
- long long int n,i,l,j,k,a,b,c,t;
- cin>>t;
- for(l=1;l<=t;l++)
- {
- cin>>n;
- int count=0;
- for(i=0;isprime[i]+isprime[i]<=(n);i++)
- {
- if(mark[n-isprime[i]]==false)
- count++;
- }
- cout<<"Case "<<l<<": "<<count<<endl;
- }
- return 0;
- }
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