Submission #1052951

#	Time	Username	Problem	Language	Result	Execution time	Memory
1052951		caterpillow	Spiral (BOI16_spiral)	C++17	0 / 100	33 ms	262144 KiB

spiral

#include <bits/stdc++.h>

using namespace std;

using db = long double;
using ll = long long;
using pl = pair<ll, ll>;
using pi = pair<int, int>;
#define vt vector
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(), x.end() 
#define size(x) ((int) (x).size())
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); i--)
#define F0R(i, b) FOR (i, 0, b)
#define endl '\n'
const ll INF = 1e18;
const int inf = 1e9;

template<typename... Args> // tuples
ostream& operator<<(ostream& os, tuple<Args...> t) { 
    apply([&](Args... args) { string dlm = "{"; ((os << dlm << args, dlm = ", "), ...); }, t);
    return os << "}";
}

template<typename T, typename V> // pairs
ostream& operator<<(ostream& os, pair<T, V> p) { return os << "{" << p.f << ", " << p.s << "}"; }

template<class T, class = decltype(begin(declval<T>()))> // iterables
typename enable_if<!is_same<T, string>::value, ostream&>::type operator<<(ostream& os, const T& v) {
    string dlm = "{";
    for (auto& i : v) os << dlm << i, dlm = ", ";
    return os << "}";  
}

template <typename T, typename... V>
void printer(string pfx, const char *names, T&& head, V&& ...tail) {
    int i = 0;
    while (names[i] && names[i] != ',') i++;
    constexpr bool is_str = is_same_v<decay_t<T>, const char*>;
    if (is_str) cerr << " " << head;
    else cerr << pfx, cerr.write(names, i) << " = " << head; 
    if constexpr (sizeof...(tail)) printer(is_str ? "" : ",", names + i + 1, tail...);
    else cerr << endl;
}

#ifdef LOCAL
#define dbg(...) printer(to_string(__LINE__) + ": ", #__VA_ARGS__, __VA_ARGS__)
#else
#define dbg(x...)
#define cerr if (0) std::cerr
#endif

const ll mod = 1e9 + 7;
void add(ll& a, ll b) {
    a = (a + b) % mod;
}

/*

subtask 1: just do it
subtask 2: find the size of the inner ring, and then math how many extra squares around the outside you are
subtask 3: 

*/

int n, q;

main() {
    cin.tie(0)->sync_with_stdio(0);
    
    cin >> n >> q;
    vt grid(2 * n + 2, vt<ll>(2 * n + 2));
    grid[n][n] = 1;
    FOR (_i, 1, n + 1) {
        int i = 2 * _i + 1;
        int x = (i - 2) * (i - 2) + 1;
        int r = n + _i;
        int c = n + _i;
        F0R (j, i - 1) r--, grid[r][c] = x++;
        F0R (j, i - 1) c--, grid[r][c] = x++;
        F0R (j, i - 1) r++, grid[r][c] = x++;
        F0R (j, i - 1) c++, grid[r][c] = x++;
    }
    // F0R (i, 2 * n + 1) {
    //     F0R (j, 2 * n + 1) {
    //         const int len = 3;
    //         string st = to_string(grid[i][j]);
    //         cerr << string(" ", len - size(st)) << st << " \n"[j == 2 * n];
    //     }
    // }
    ROF (i, 0, 2 * n + 1) ROF (j, 0, 2 * n + 1) add(grid[i][j], grid[i + 1][j]);
    ROF (i, 0, 2 * n + 1) ROF (j, 0, 2 * n + 1) add(grid[i][j], grid[i][j + 1]);

    F0R (i, q) {
        int r1, r2, c1, c2; 
        cin >> c1 >> r2 >> c2 >> r1;
        r1 += n, c1 += n, r2 += n, c2 += n;
        r1 = 2 * n - r1;
        r2 = 2 * n - r2;
        ll ans = grid[r1][c1] - grid[r1][c2 + 1] - grid[r2 + 1][c1] + grid[r2 + 1][c2 + 1];
        cout << (ans % mod) << endl;
    }
}

Compilation message (stderr)

spiral.cpp:71:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   71 | main() {
      | ^~~~

• Subtask 1: 0 / 12
• Subtask 2: 0 / 15
• Subtask 3: 0 / 17
• Subtask 4: 0 / 31
• Subtask 5: 0 / 25