Submission #1052366

#	Time	Username	Problem	Language	Result	Execution time	Memory
1052366		crafticat	Monster Game (JOI21_monster)	C++17	0 / 100	41 ms	780 KiB

monster

#include <bits/stdc++.h>

using namespace std;

#include <bits/stdc++.h>

#include <utility>
using namespace std;

using ll = long long;
using pi = pair<int,int>;
using pl = pair<ll,ll>;

#define temp(T) template<class T>
temp(T) using V = vector<T>;
using vi = V<int>;
using vl = V<ll>;
using vvi = V<vi>;
using vpi = V<pi>;
using vb = V<bool>;
using vvb = V<vb>;
vi dx = {0,1,-1,0};
vi dy = {1,0,0,-1};

#define sz(x) x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define pb push_back
#define eb emplace_back
#define f first
#define s second

#define lb lower_bound
#define ub upper_bound

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)

using str = string;

const int MOD = 1e9 + 7;
const ll BIG = 1e18;
const int INF = 1e9 + 2;

temp(T) bool ckmin(T& a, const T& b) {
    return b < a ? a = b, 1 : 0; } // set a = min(a,b)
temp(T) bool ckmax(T& a, const T& b) {
    return a < b ? a = b, 1 : 0; } // set a = max(a,b)

void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
// FILE I/O
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void setIO(str s = "") {
    unsyncIO();
    if (sz(s)) setIn(s+".in"), setOut(s+".out"); // for USACO
}

#define read(x) int x; cin >> x

temp(T) void pr(T x) {
    cout << to_string(x);
}
temp(T) void prln(T x) {
    cout << to_string(x) << "\n";
}


vi readV(int n) {

    vi input(n);
    F0R(i,n)
        cin >> input[i];
    return input;
}

int rand(int a, int b) {
    return a + rand() % (b - a + 1);
}

#define gen(x,a,b) int x = rand(a,b)

temp(T) void moveAll(V<T> &a, V<T> &b) {
    each(x,b) {
        a.pb(x);
    }
    b.clear();
}

vi genArr(int n, int a, int b) {
    vi generated(n);
    F0R(i,n) {
        generated[i] = rand(a,b);
    }
    return generated;
}

vvi genTree(int n) {
    vvi g(n + 1);
    F0R(i,n) {
        gen(p,0,i);
        g[p].pb(i + 1);
        g[i + 1].pb(p);
    }

    return g;
}

vvb readGrid(int a, int b) {
    vvb grid(a + 2, vb(b + 2, true));

    F0R(i, a) {
        F0R(j, b) {
            bool k; cin >> k;
            grid[i + 1][j + 1] = k;
        }
    }
    return grid;
}

bool Query(int a, int b);

int findBest(int a, int b) {
    if (a == -1) return b;
    if (b == -1) return a;
    return (Query(a,b)) ? b : a;
}

struct Seg {
    Seg *left = nullptr, *right = nullptr;
    int l, r, mid;
    int v;

    Seg(int l, int r) : l(l), r(r), mid((r + l) / 2) {
        if (r - l > 1) {
            left = new Seg(l,mid);
            right = new Seg(mid,r);
            v = findBest(left->v, right->v);
        } else v = l;
    }

    void update(int k) {
        if (r - l <= 1) {
            v = -1;
            return;
        }

        if (k < mid)
            left->update(k);
        else
            right->update(k);
        v = findBest(left->v, right->v);
    }
};

int n;
vi arr;

int findNext(int l) {
    if (l >= n - 1) return 1; // Edge literally
    int siz = 2;
    if (Query(arr[l], arr[l + 1])) return 1;
    while (l + siz < n && Query(arr[l], arr[l + siz])) {
        siz++;
    }
    return siz;
}

void flip(int l, int j) {
    F0R(i, (j + 1) / 2) {
        swap(arr[l + i], arr[l + (j - i)]);
    }
}

vi edges;

void fix(int l) {
    while (l < n) {
        int nextJ = findNext(l);
        if (nextJ == 1) {
            edges.pb(l);
            l += nextJ;
            if (l >= n) return;
            continue;
        }

        edges.pb(l);
        edges.pb(l + nextJ - 1);
        if (nextJ > 3 && !Query(l + 1, l + nextJ - 1)) {
            nextJ--;
        } else {
            if (sz(edges) == 2) {
                fix(l + nextJ);
            } else {
                int p1 = edges[sz(edges) - 3];
                int p2 = edges[sz(edges) - 4];
                if (!Query(arr[p1], arr[l + nextJ - 1]) and !Query(arr[p2], arr[l + nextJ - 1])) {
                    nextJ--;
                }
            }
        }

        flip(l, nextJ - 1);
        l += nextJ;
    }
}

std::vector<int> Solve(int N) {
    Seg seg(0, N);
    while (seg.v != -1) {
        arr.pb(seg.v);
        seg.update(seg.v);
    }

    n = N;
    fix(0);
    vi ans(n);
    F0R(i, n) {
        ans[arr[i]] = i;
    }
    return ans;
}

#ifdef DEBUG
namespace {

using std::exit;
using std::fprintf;
using std::printf;
using std::scanf;

constexpr int Q_MAX = 25'000;
constexpr int N_MAX = 1'000;

int N;
int S[N_MAX];

int query_count = 0;

void WrongAnswer(int code) {
  printf("Wrong Answer [%d]\n", code);
  exit(0);
}

}  // namespace

bool Query(int a, int b) {
  if (++query_count > Q_MAX) WrongAnswer(6);
  if (a < 0 || N <= a || b < 0 || N <= b) WrongAnswer(4);
  if (a == b) WrongAnswer(5);
  return (S[a] > S[b]) ^ (abs(S[a] - S[b]) == 1);
}

int main() {
  if (scanf("%d", &N) != 1) {
    fprintf(stderr, "Error while reading.\n");
    exit(1);
  }
  for (int i = 0; i < N; i++) {
    if (scanf("%d", S + i) != 1) {
      fprintf(stderr, "Error while reading.\n");
      exit(1);
    }
  }
  std::vector<int> T = Solve(N);
  if ((int)T.size() != N) WrongAnswer(1);
  for (int i = 0; i < N; i++) {
    if (T[i] < 0 || N <= T[i]) WrongAnswer(2);
    if (T[i] != S[i]) WrongAnswer(3);
  }
  printf("Accepted: %d\n", query_count);
  return 0;
}

#endif

Compilation message (stderr)

monster.cpp: In function 'void setIn(str)':
monster.cpp:59:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
monster.cpp: In function 'void setOut(str)':
monster.cpp:60:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 15
• Subtask 3: 0 / 75