#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- const int prime_max = 1000000; vector prime; int ok[1505050]; int NP,divp[prime_max]; void cprime() { if(NP) return; for(int i=2;i=i&&j>N; for(i=0;prime[i]<=N;i++) { for(j=i;prime[j]<=N;j++) { if(ok[prime[i]+prime[j]]) ret+=1+(i!=j); } } cout<