#include <iostream> #include <cmath> #include <set> using namespace std; set< set<int> > primitives; int nwd(int a, int b) { if(a == 0) return b; if(b == 0) return a; return nwd(b,a%b); } int nwd(int a, int b, int c, int d) { return nwd(nwd(a,b), nwd(c,d)); } const int PIERW5000 = round(sqrt(5000))+1; int main() { int nn; cin >> nn; int licznik = 0; for(int n = 0; n < PIERW5000; n++) for(int m = 0; m < PIERW5000; m++) for(int q = 0; q < PIERW5000; q++) for(int p = 0; p < PIERW5000; p++) { if( (m+n+p+q) % 2 == 0 || nwd(m,n,p,q) != 1) continue; int a = m*m + n*n - p * p - q*q; int b = 2*(m*q + n * p); int c = 2*(n*q-m*p); int d = m*m + n*n + p*p + q*q; if(a <= 0 || b <= 0 || c <= 0) continue; if(nwd(a,b,c,d) != 1) continue; if(d > nn) break; set<int> s = {a,b,c}; if( primitives.find(s) == primitives.end() ) { primitives.insert(s); int krotnosc = nn / d; if(a == b && b == c) { licznik += krotnosc; } else { if(a == b || b == c || a == c) { licznik += krotnosc * 2; } else { licznik += krotnosc * 3; } } } } cout << licznik << endl; 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 | #include <iostream> #include <cmath> #include <set> using namespace std; set< set<int> > primitives; int nwd(int a, int b) { if(a == 0) return b; if(b == 0) return a; return nwd(b,a%b); } int nwd(int a, int b, int c, int d) { return nwd(nwd(a,b), nwd(c,d)); } const int PIERW5000 = round(sqrt(5000))+1; int main() { int nn; cin >> nn; int licznik = 0; for(int n = 0; n < PIERW5000; n++) for(int m = 0; m < PIERW5000; m++) for(int q = 0; q < PIERW5000; q++) for(int p = 0; p < PIERW5000; p++) { if( (m+n+p+q) % 2 == 0 || nwd(m,n,p,q) != 1) continue; int a = m*m + n*n - p * p - q*q; int b = 2*(m*q + n * p); int c = 2*(n*q-m*p); int d = m*m + n*n + p*p + q*q; if(a <= 0 || b <= 0 || c <= 0) continue; if(nwd(a,b,c,d) != 1) continue; if(d > nn) break; set<int> s = {a,b,c}; if( primitives.find(s) == primitives.end() ) { primitives.insert(s); int krotnosc = nn / d; if(a == b && b == c) { licznik += krotnosc; } else { if(a == b || b == c || a == c) { licznik += krotnosc * 2; } else { licznik += krotnosc * 3; } } } } cout << licznik << endl; return 0; } |