#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//#pragma GCC optimize("O0")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,tune=native")
#pragma GCC optimize("unroll-loops")
using namespace std;
//using namespace __gnu_pbds;
#define pb push_back
#define F first
#define S second
#define ll long long
#define ld double long
#define ull unsigned long long
//#define endl '\n'
const ll N = 5e4 + 36;
const ll M = 2e3 + 36;
const ll INF = 1e9 + 7;
const ll MOD = 1e9 + 7;
const ll MOD1 = 888888901;
const ll MOD2 = 999988901;
const ll X[8] = {1, -1, 2, 2, -2, -2, 1, -1};
const ll Y[8] = {2, 2, 1, -1, 1, -1, -2, -2};
const ld PI = 3.14159265358979323846;
const ld EPS = 1e-10;
//tree < pair < string, int >, null_type, less < pair < string, int > >, rb_tree_tag, tree_order_statistics_node_update > a;
//mt19937 gen(chrono::system_clock::now().time_since_epoch().count());
mt19937 gen(19937);
signed main() {
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#else
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
#endif // LOCAL
int n = 5000;
cin >> n;
int ss = sqrt((n * n) * 3);
vector<int> mp(50000001, 0);
vector<pair<int, int>> lol;
for (int i(1); i <= n; ++i) {
for (int j(1); j <= n; ++j) {
mp[i * i + j * j]++;
lol.pb({i, i * i + j * j});
}
}
reverse(lol.begin(), lol.end());
int k = 0;
/*for (int i(1); i <= n; ++i){
for (int j(i); j <= n; ++j) {
for (int l(1); l <= n; ++l) {
ll x = i * i + j * j + l * l;
//if (sqr.find(x) != sqr.end()) {
int y = sqrt(x);
if (y <= n && y * y == x) {
++k;
cout << i << ' ' << j << ' ' << l << endl;
}
//}
}
}
}
cout << k << endl;*/
int ans = 0;
for (int i(1); i <= n; ++i) {
for (int j(i); j <= n; ++j) {
if (50000000 >= j * j - i * i)
ans += mp[j * j - i * i];
}
while (lol.size() && lol.back().F == i) {
--mp[lol.back().S];
lol.pop_back();
}
}
cout << ans << 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 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 | #include <bits/stdc++.h> //#include <ext/pb_ds/assoc_container.hpp> //#include <ext/pb_ds/tree_policy.hpp> //#pragma GCC optimize("O0") //#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,tune=native") #pragma GCC optimize("unroll-loops") using namespace std; //using namespace __gnu_pbds; #define pb push_back #define F first #define S second #define ll long long #define ld double long #define ull unsigned long long //#define endl '\n' const ll N = 5e4 + 36; const ll M = 2e3 + 36; const ll INF = 1e9 + 7; const ll MOD = 1e9 + 7; const ll MOD1 = 888888901; const ll MOD2 = 999988901; const ll X[8] = {1, -1, 2, 2, -2, -2, 1, -1}; const ll Y[8] = {2, 2, 1, -1, 1, -1, -2, -2}; const ld PI = 3.14159265358979323846; const ld EPS = 1e-10; //tree < pair < string, int >, null_type, less < pair < string, int > >, rb_tree_tag, tree_order_statistics_node_update > a; //mt19937 gen(chrono::system_clock::now().time_since_epoch().count()); mt19937 gen(19937); signed main() { ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0); #ifdef LOCAL freopen("input.txt", "r", stdin); freopen("output.txt", "w", stdout); #else // freopen("input.txt", "r", stdin); // freopen("output.txt", "w", stdout); #endif // LOCAL int n = 5000; cin >> n; int ss = sqrt((n * n) * 3); vector<int> mp(50000001, 0); vector<pair<int, int>> lol; for (int i(1); i <= n; ++i) { for (int j(1); j <= n; ++j) { mp[i * i + j * j]++; lol.pb({i, i * i + j * j}); } } reverse(lol.begin(), lol.end()); int k = 0; /*for (int i(1); i <= n; ++i){ for (int j(i); j <= n; ++j) { for (int l(1); l <= n; ++l) { ll x = i * i + j * j + l * l; //if (sqr.find(x) != sqr.end()) { int y = sqrt(x); if (y <= n && y * y == x) { ++k; cout << i << ' ' << j << ' ' << l << endl; } //} } } } cout << k << endl;*/ int ans = 0; for (int i(1); i <= n; ++i) { for (int j(i); j <= n; ++j) { if (50000000 >= j * j - i * i) ans += mp[j * j - i * i]; } while (lol.size() && lol.back().F == i) { --mp[lol.back().S]; lol.pop_back(); } } cout << ans << endl; return 0; } |
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