#include <bits/stdc++.h>
#define e using u=ostream;template<class a,class b>u&operator<<(u&o,pair<a,b>&x)
using namespace std;e;u&operator<<(u&o,string&s){return o<<s.c_str();}template<
class t>auto operator<<(u&o,t&x)->decltype(x.end(),o){o<<'{';int i=2;for(auto y:
x)o<<", "+i<<y,i=0;return o<<'}';}e{return o<<'('<<x.first<<", "<<x.second<<')';}
#ifdef DEBUG
#define LOG(x...)cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x)
#else
#define LOG(...)
#endif
#define ff first
#define ss second
#define ll long long
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
set <ll> squares;
vector <int> suma(50000001);
for (ll i = 1; i <= 5000; i++) {
for (ll j = i; j <= 5000; j++) {
suma[i*i+j*j]++;
}
}
ll n;
ll res = 0;
cin >> n;
for (ll i = 1; i <= n; i++) {
for (ll j = 1; j <= 5000; j++) {
if (i*i-j*j >= 0 && suma[i*i-j*j] != 0) {
// cout << i << " " << j << " " << i*i-j*j << "\n";
res += suma[i*i-j*j];
}
}
}
cout << res << "\n";
}
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 | #include <bits/stdc++.h> #define e using u=ostream;template<class a,class b>u&operator<<(u&o,pair<a,b>&x) using namespace std;e;u&operator<<(u&o,string&s){return o<<s.c_str();}template< class t>auto operator<<(u&o,t&x)->decltype(x.end(),o){o<<'{';int i=2;for(auto y: x)o<<", "+i<<y,i=0;return o<<'}';}e{return o<<'('<<x.first<<", "<<x.second<<')';} #ifdef DEBUG #define LOG(x...)cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...)<<'\n';}(x) #else #define LOG(...) #endif #define ff first #define ss second #define ll long long int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); set <ll> squares; vector <int> suma(50000001); for (ll i = 1; i <= 5000; i++) { for (ll j = i; j <= 5000; j++) { suma[i*i+j*j]++; } } ll n; ll res = 0; cin >> n; for (ll i = 1; i <= n; i++) { for (ll j = 1; j <= 5000; j++) { if (i*i-j*j >= 0 && suma[i*i-j*j] != 0) { // cout << i << " " << j << " " << i*i-j*j << "\n"; res += suma[i*i-j*j]; } } } cout << res << "\n"; } |
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