#include <cstdio>
#include <cstring>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <bitset>
#include <utility>
#include <stack>
#include <unordered_set>
using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
typedef vector<int> VI;
#define MP make_pair
#define FOR(v,p,k) for(int v=(p);v<=(k);++v)
#define FORD(v,p,k) for(int v=(p);v>=(k);--v)
#define REP(i,n) for(int i=0;i<(n);++i)
#define VAR(v,i) __typeof(i) v=(i)
#define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i)
#define PB push_back
#define ST first
#define ND second
#define SIZE(x) (int)x.size()
#define ALL(c) c.begin(),c.end()
#define ODD(x) ((x)%2)
#define EVEN(x) (!(ODD(x)))
class Primes {
public:
VI primes;
VI tmp;
int max_n;
VI is_prime;
Primes(int max_n) : max_n(max_n), is_prime(max_n+1, 1) {
is_prime[0]=is_prime[1]=0;
int p=2;
int j=p*p;
while (j<=max_n) {
int k=j;
while (k<=max_n) {
is_prime[k]=0;
k+=p;
}
p+=1;
while (!is_prime[p]) {
p+=1;
}
j=p*p;
}
REP(i, max_n+1) {
if (is_prime[i]) {
primes.PB(i);
}
}
}
void fill_prime_divisors(int n, VI &divisors) {
int max_prime = (int) floor(sqrt(n));
assert(max_prime <= max_n);
FOREACH(i, primes) {
if (*i > max_prime) break;
while ((n % *i) == 0) {
divisors.PB(*i);
n /= *i;
}
}
}
void fill_small_prime_and_all_divisors(int n, VI &prime_divisors, unordered_set<int> &divisors) {
fill_prime_divisors(n, prime_divisors);
divisors.insert(1);
FOREACH(i, prime_divisors) {
tmp.clear();
FOREACH(d, divisors) {
tmp.PB((*d)* (*i));
}
std::copy(tmp.begin(),tmp.end(),std::inserter(divisors, divisors.end()));
}
tmp.clear();
FOREACH(i, divisors) {
tmp.PB(n/(*i));
}
std::copy(tmp.begin(),tmp.end(),std::inserter(divisors, divisors.end()));
}
};
int main() {
int n;
scanf("%d", &n);
LL res = 0LL;
Primes primes((int) floor(sqrt(n)));
VI prime_divisors, prime_divisors2;
unordered_set<int> divisors, divisors2;
primes.fill_small_prime_and_all_divisors(n, prime_divisors, divisors);
FOREACH(a, divisors) {
int na = n/(*a) -1;
if (na < 6 ) continue;
prime_divisors2.clear();
divisors2.clear();
primes.fill_small_prime_and_all_divisors(na, prime_divisors2, divisors2);
FOREACH(bb, divisors2) {
int cc = na/(*bb) - 1;
if ((*bb > 1) && (cc > 1)) ++res;
}
}
printf("%lld\n", res);
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 | #include <cstdio> #include <cstring> #include <cmath> #include <cassert> #include <iostream> #include <algorithm> #include <iterator> #include <string> #include <vector> #include <queue> #include <bitset> #include <utility> #include <stack> #include <unordered_set> using namespace std; typedef long long LL; typedef pair<int,int> PII; typedef vector<int> VI; #define MP make_pair #define FOR(v,p,k) for(int v=(p);v<=(k);++v) #define FORD(v,p,k) for(int v=(p);v>=(k);--v) #define REP(i,n) for(int i=0;i<(n);++i) #define VAR(v,i) __typeof(i) v=(i) #define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i) #define PB push_back #define ST first #define ND second #define SIZE(x) (int)x.size() #define ALL(c) c.begin(),c.end() #define ODD(x) ((x)%2) #define EVEN(x) (!(ODD(x))) class Primes { public: VI primes; VI tmp; int max_n; VI is_prime; Primes(int max_n) : max_n(max_n), is_prime(max_n+1, 1) { is_prime[0]=is_prime[1]=0; int p=2; int j=p*p; while (j<=max_n) { int k=j; while (k<=max_n) { is_prime[k]=0; k+=p; } p+=1; while (!is_prime[p]) { p+=1; } j=p*p; } REP(i, max_n+1) { if (is_prime[i]) { primes.PB(i); } } } void fill_prime_divisors(int n, VI &divisors) { int max_prime = (int) floor(sqrt(n)); assert(max_prime <= max_n); FOREACH(i, primes) { if (*i > max_prime) break; while ((n % *i) == 0) { divisors.PB(*i); n /= *i; } } } void fill_small_prime_and_all_divisors(int n, VI &prime_divisors, unordered_set<int> &divisors) { fill_prime_divisors(n, prime_divisors); divisors.insert(1); FOREACH(i, prime_divisors) { tmp.clear(); FOREACH(d, divisors) { tmp.PB((*d)* (*i)); } std::copy(tmp.begin(),tmp.end(),std::inserter(divisors, divisors.end())); } tmp.clear(); FOREACH(i, divisors) { tmp.PB(n/(*i)); } std::copy(tmp.begin(),tmp.end(),std::inserter(divisors, divisors.end())); } }; int main() { int n; scanf("%d", &n); LL res = 0LL; Primes primes((int) floor(sqrt(n))); VI prime_divisors, prime_divisors2; unordered_set<int> divisors, divisors2; primes.fill_small_prime_and_all_divisors(n, prime_divisors, divisors); FOREACH(a, divisors) { int na = n/(*a) -1; if (na < 6 ) continue; prime_divisors2.clear(); divisors2.clear(); primes.fill_small_prime_and_all_divisors(na, prime_divisors2, divisors2); FOREACH(bb, divisors2) { int cc = na/(*bb) - 1; if ((*bb > 1) && (cc > 1)) ++res; } } printf("%lld\n", res); return 0; } |
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