59 lines
1.0 KiB
C++
59 lines
1.0 KiB
C++
#include<iostream>
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#include<cmath>
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#include<cstring>
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#include<vector>
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using namespace std;
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const int maxn=100005;
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int useable[maxn];
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void get_primes(int n,vector<int> &primes)
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{
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int m=int(sqrt(n)+0.5);
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for(int i=2;i<=m;i++)
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if(n%i==0)
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{
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primes.push_back(i);
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while(n%i==0) n/=i;
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}
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if(n>1) primes.push_back(n);
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}
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int main()
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{
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#ifdef local
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freopen("pro.in","r",stdin);
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#endif
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int n,m,kase=0;
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while(cin>>n>>m)
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{
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vector<int> primes;
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get_primes(m,primes);
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memset(useable,0,sizeof(useable));
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n--;
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for(int i=0;i<primes.size();i++)
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{
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int p=primes[i],e=0;//C(n,0) = p^e
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int min_e=0,x=m;
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while(x%p==0) {x/=p; min_e++;}
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//C(n,k)=C(n,k-1)*(n-k+1)/k
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for(int k=1;k<n;k++)
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{
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x=n-k+1;
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while(x%p==0) {x/=p; e++;}
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x=k;
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while(x%p==0) {x/=p; e--;}
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if(e<min_e) useable[k]=1;
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}
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}
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vector<int> res;
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for(int k=1;k<n;k++)
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if(!useable[k]) res.push_back(k+1);
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cout<<res.size()<<"\n";
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if(!res.empty())
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{
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cout<<res[0];
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for(int i=1;i<res.size();i++) cout<<' '<<res[i];
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}
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cout<<"\n";
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}
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return 0;
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}
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