제출 #320245

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
320245		VROOM_VARUN	Shortcut (IOI16_shortcut)	C++14	컴파일 에러	0 ms	0 KiB

shortcut

/*
ID: varunra2
LANG: C++
TASK: shortcut
*/

#include<bits/stdc++.h>
#include "shortcut.h"
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define int long long

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e16
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define trav(a, x) for(auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

VI l;
VI x;
VI d;
VII ord;
vector<bool> dom;
VI doms;
int n;
int c;


void cop(VI& a, vector<int32_t> b) {
  a.resize(sz(b));
  for(int i = 0; i < sz(a); i++) {
    a[i] = b[i];
  }
}

void genPref() {
  x.resize(n);
  x[0] = 0ll;
  for(int i = 1; i < n; i++) {
    x[i] = x[i - 1] + l[i - 1];
  }
}

void genDom() {
  // here we need to generate statinos that are not dominated by anybody
  // then x[dom[i]] + d[dom[i]] is non decreasing
  dom.assign(n, true);
  // to do this, we need to generate prefix and suffix maxima of stuff lol
  int mx = -INF;
  for(int i = 0; i < n; i++) {
    int cur = d[i] + x[i];
    mx = max(mx, cur);
    if(cur < mx) dom[i] = false;
  }
  int mx = -INF;
  for(int i = n - 1; i >= 0; i--) {
    int cur = d[i] - x[i];
    mx = max(mx, cur);
    if(cur < mx) dom[i] = false;
  }
  for(int i = 0; i < n; i++) {
    if(dom[i]) doms.PB(i);
  }
  assert(!doms.empty());
}

void genOrd() {
  // we also need to generate a sorted vector of pairs that contains when the ith element is introduced, and its index
  ord.resize(n);
  for(int i = 0; i < n; i++) {
    ord[i] = MP(x[i] - d[i], i);
  }
  sort(all(ord));
}

int mnsum, mxsum, mndif, mxdif;

void upd(int i) {
  int x = ::x[i], d = ::d[i];
  int sum = x + d, dif = x - d;
  mnsum = min(mnsum, sum);
  mxsum = max(mxsum, sum);
  mndif = min(mndif, dif);
  mxdif = max(mxdif, dif);
}

bool works(int k) {
  VI vals = {INF, -INF, INF, -INF};  
  mnsum = INF;
  mxsum = -INF;
  mndif = INF;
  mxdif = -INF;
  int p1 = 0;
  for(int i = 0; i < n; i++) {
    if(dom[i] == false) continue;
    while(p1 < n and ord[p1].x < x[i] + d[i] - k and ord[p1].y <= i) {
      // now we process it
      upd(p1);
      p1++;
    }
    int sum = x[i] + d[i], dif = x[i] - d[i];
    vals[0] = min(vals[0], (k - c) + dif + mndif);
    vals[1] = max(vals[1], sum + mxsum - (k - c));
    vals[2] = min(vals[2], (k - c) + dif - mxsum);
    vals[3] = max(vals[3], sum - mndif - (k - c));
  }

  // now we need to find two points in the rectangle defined by vals
  int maxsum, minsum, maxdif, mindif;
  maxsum = vals[0];
  minsum = vals[1];
  maxdif = vals[2];
  mindif = vals[3];
  int curdif = 0;
  int cursum = n;
  if(maxsum < minsum or maxdif < mindif) return 0;
  for(int i = 0; i < n; i++) {
    while(curdif < n and x[curdif] - x[i] < mindif) curdif++;
    while(cursum > 0 and x[cursum - 1] + x[i] >= minsum) cursum--;
    int cur = max({cursum, curdif, i + 1});
    if(cur < n and x[cur] + x[i] <= maxsum and x[cur] - x[i] <= maxdif) return true;
  }
  return false;
}

ll find_shortcut(int32_t _n, vector<int32_t> _l, vector<int32_t> _d, int32_t _c) {
  n = _n;
  c = _c;
  cop(l, _l);
  cop(d, _d);
  genPref();
  genDom();
  genOrd();
  int xx = -1;
  int z = 1e16;
  for(int b = z; b >= 1; b /= 2) {
    while(!works(xx + b)) xx += b;
  }
  return xx + 1;
}

// int32_t main() {
// #ifndef ONLINE_JUDGE
//   freopen("shortcut.in", "r", stdin);
//   freopen("shortcut.out", "w", stdout);
// #endif
//   cin.sync_with_stdio(0); cin.tie(0);

//   return 0;
// }

컴파일 시 표준 에러 (stderr) 메시지

shortcut.cpp: In function 'void genDom()':
shortcut.cpp:94:7: error: redeclaration of 'long long int mx'
   94 |   int mx = -INF;
      |       ^~
shortcut.cpp:88:7: note: 'long long int mx' previously declared here
   88 |   int mx = -INF;
      |       ^~