#include <bits/stdc++.h> using namespace std; #define rng(i,a,b) for(int i=int(a);i<=int(b);i++) #define rep(i,b) rng(i,0,b-1) #define gnr(i,b,a) for(int i=int(b);i>=int(a);i--) #define per(i,b) gnr(i,b-1,0) #define pb push_back #define eb emplace_back #define fi first #define se second #define bg begin() #define ed end() #define all(x) x.bg,x.ed #define si(x) int(x.size()) template<class t> using vc=vector<t>; template<class t> using vvc=vc<vc<t>>; typedef long long ll; using pii=pair<int,int>; using vi=vc<int>; using uint=unsigned; using ull=unsigned long long; using pil=pair<int,ll>; using pli=pair<ll,int>; using pll=pair<ll,ll>; using t3=tuple<int,int,int>; ll rand_int(ll l, ll r) { //[l, r] #ifdef LOCAL static mt19937_64 gen; #else static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count()); #endif return uniform_int_distribution<ll>(l, r)(gen); } template <uint MD> struct ModInt { using M = ModInt; const static M G; uint v; ModInt(ll _v = 0) { set_v(_v % MD + MD); } M& set_v(uint _v) { v = (_v < MD) ? _v : _v - MD; return *this; } explicit operator bool() const { return v != 0; } M operator-() const { return M() - *this; } M operator+(const M& r) const { return M().set_v(v + r.v); } M operator-(const M& r) const { return M().set_v(v + MD - r.v); } M operator*(const M& r) const { return M().set_v(ull(v) * r.v % MD); } M operator/(const M& r) const { return *this * r.inv(); } M& operator+=(const M& r) { return *this = *this + r; } M& operator-=(const M& r) { return *this = *this - r; } M& operator*=(const M& r) { return *this = *this * r; } M& operator/=(const M& r) { return *this = *this / r; } bool operator==(const M& r) const { return v == r.v; } M pow(ll n) const { M x = *this, r = 1; while (n) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; } M inv() const { return pow(MD - 2); } friend ostream& operator<<(ostream& os, const M& r) { return os << r.v; } }; using Mint = ModInt<998244353>; using t4 = tuple<int,int,int,int>; using t5 = tuple<int,int,int,int,int>; #define N_ 201000 int C[25100000]; void Solve(){ int n; scanf("%d",&n); rng(i,1,n){ rng(j,i,n){ if(i*i+j*j>n*n)break; C[i*i+j*j]++; } } ll ans=0; rng(i,1,n){ rng(j,1,i-1){ ans += C[i*i-j*j]; } } printf("%lld\n",ans); } int main(){ int TC=1; //scanf("%d",&TC); while(TC--){ Solve(); } }
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 | #include <bits/stdc++.h> using namespace std; #define rng(i,a,b) for(int i=int(a);i<=int(b);i++) #define rep(i,b) rng(i,0,b-1) #define gnr(i,b,a) for(int i=int(b);i>=int(a);i--) #define per(i,b) gnr(i,b-1,0) #define pb push_back #define eb emplace_back #define fi first #define se second #define bg begin() #define ed end() #define all(x) x.bg,x.ed #define si(x) int(x.size()) template<class t> using vc=vector<t>; template<class t> using vvc=vc<vc<t>>; typedef long long ll; using pii=pair<int,int>; using vi=vc<int>; using uint=unsigned; using ull=unsigned long long; using pil=pair<int,ll>; using pli=pair<ll,int>; using pll=pair<ll,ll>; using t3=tuple<int,int,int>; ll rand_int(ll l, ll r) { //[l, r] #ifdef LOCAL static mt19937_64 gen; #else static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count()); #endif return uniform_int_distribution<ll>(l, r)(gen); } template <uint MD> struct ModInt { using M = ModInt; const static M G; uint v; ModInt(ll _v = 0) { set_v(_v % MD + MD); } M& set_v(uint _v) { v = (_v < MD) ? _v : _v - MD; return *this; } explicit operator bool() const { return v != 0; } M operator-() const { return M() - *this; } M operator+(const M& r) const { return M().set_v(v + r.v); } M operator-(const M& r) const { return M().set_v(v + MD - r.v); } M operator*(const M& r) const { return M().set_v(ull(v) * r.v % MD); } M operator/(const M& r) const { return *this * r.inv(); } M& operator+=(const M& r) { return *this = *this + r; } M& operator-=(const M& r) { return *this = *this - r; } M& operator*=(const M& r) { return *this = *this * r; } M& operator/=(const M& r) { return *this = *this / r; } bool operator==(const M& r) const { return v == r.v; } M pow(ll n) const { M x = *this, r = 1; while (n) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; } M inv() const { return pow(MD - 2); } friend ostream& operator<<(ostream& os, const M& r) { return os << r.v; } }; using Mint = ModInt<998244353>; using t4 = tuple<int,int,int,int>; using t5 = tuple<int,int,int,int,int>; #define N_ 201000 int C[25100000]; void Solve(){ int n; scanf("%d",&n); rng(i,1,n){ rng(j,i,n){ if(i*i+j*j>n*n)break; C[i*i+j*j]++; } } ll ans=0; rng(i,1,n){ rng(j,1,i-1){ ans += C[i*i-j*j]; } } printf("%lld\n",ans); } int main(){ int TC=1; //scanf("%d",&TC); while(TC--){ Solve(); } } |