Submission #1113435

#	Time	Username	Problem	Language	Result	Execution time	Memory
1113435		ntdaccode	Real Mountains (CCO23_day1problem2)	C++17	25 / 25	2745 ms	182860 KiB

Main

#include<bits/stdc++.h>
#define fori(i,a,b) for(int i = a;i <= b; i++)
#define int long long
#define pb push_back
using namespace std;

typedef pair<int,int> ii;
typedef tuple<int,int,int> tp;

const int M = 1e6 + 10;
const int N = 5e3 + 10;
const int mod = 1e6 + 3;

int n,h[M];
int target[M];
vector<int> in[M],out[M];
vector<int> rrh;

int calc(int l,int r) {
  return ((l + r) * (r - l + 1) / 2) % mod;
}

int t[4 * M];
void build(int s,int l, int r)
{
  if(l == r) {
    t[s] = h[l];
    return ;
  }
  int mid = (l + r)/2;
  build(s * 2,l,mid);
  build(s * 2 + 1, mid + 1, r);
  t[s] = min(t[s * 2] , t[s * 2 + 1]);
}

void upd(int s,int l, int r, int pos, int val)
{
  if(l > pos || pos > r) return ;
  if(l == r) {
    t[s] = val;
    return ;
  }
  int mid = (l + r)/2;
  upd(s * 2, l, mid, pos, val);
  upd(s * 2 + 1, mid + 1, r, pos, val);
  t[s] = min(t[s * 2],t[s * 2 + 1]);
}

int get(int s, int l, int r, int u, int v)
{
  if(l > v || r < u) return 1e9;
  if(u <= l && r <= v) return t[s];
  int mid = (l + r)/2;
  return min(get(s * 2, l, mid, u, v),get(s * 2 + 1, mid + 1, r, u, v));
}

int32_t main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  if(fopen("1.inp","r"))
  {
    freopen("1.inp","r",stdin);
    freopen("1.out","w",stdout);
  }
  #define task ""
  if(fopen(task".inp","r"))
  {
    freopen(task".inp","r",stdin);
    freopen(task".out","w",stdout);
  }
  cin >> n;
  for(int i = 1;i <= n; i++) cin >> h[i];
  build(1,1,n);

  int suf = 0,pre = 0;
  for(int i = 1;i <= n; i++) {
    pre = max(pre, h[i]);
    target[i] =  pre ;
  }
  for(int i = n; i != 0; i--) {
    suf = max(suf, h[i]);
    target[i] = min(target[i], suf);
  }

  for(int i = 1;i <= n; i++) rrh.pb(h[i]);
  sort(rrh.begin(),rrh.end());
  rrh.resize(unique (rrh.begin(), rrh.end()) - rrh.begin());
  for(int i = 1;i <= n; i++) {
      h[i] = lower_bound(rrh.begin(),rrh.end(),h[i]) - rrh.begin() ;
      target[i] = lower_bound(rrh.begin(),rrh.end(),target[i]) - rrh.begin() ;
      if(h[i] != target[i]) {
        out[target[i]].pb(i);
      }
      in[h[i]].pb(i);

  }


  int kq = 0;
  int m= rrh.size();
  set<int> s;

  for(int high = 0;high <= m - 2; high ++) {

    for(int idx : in[high]) {
        if(h[idx] != target[idx]) s.insert(idx);
        upd(1,1,n,idx,1e9);
    }

    int sz = s.size();
    if(sz == 0) continue;
    int val = rrh[high] % mod;
    int nxt_val = rrh[high + 1] % mod;
    if(sz == 1) {

      int cur = *s.begin();
      int x = get(1, 1, n, 1, cur - 1) , y = get(1, 1, n, cur + 1, n);
      x %= mod;
      y %= mod;

      kq = (kq + (nxt_val - val)*(x + y) % mod  ) % mod;

    }
    else {

      int l = *s.begin(), r = *s.rbegin();

      int pre_l = get(1, 1, n, 1, l - 1) , pre_r = get(1, 1, n, 1, r - 1) ,
      suf_l = get(1, 1, n, l + 1, n) , suf_r = get(1, 1, n, r + 1, n);

      int x =(rrh[high + 1] - rrh[high]) * (pre_l + suf_l) + (rrh[high + 1] - rrh[high]) * suf_r ;
      int y =(rrh[high + 1] - rrh[high]) * (pre_r + suf_r) + (rrh[high + 1] - rrh[high]) * pre_l ;

      x = min(x,y) % mod;
      kq = (kq + x) % mod;

      kq = ( kq + (sz - 2) * 2ll * calc(val + 1 ,nxt_val) % mod + calc(val + 1,nxt_val)) % mod;
    }

    kq = (kq + sz * calc(val,nxt_val - 1) % mod) % mod;


    for(int idx : out[high + 1]) s.erase(idx);

  }
  cout << (kq + mod) % mod;
}

Compilation message (stderr)

Main.cpp: In function 'int32_t main()':
Main.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |     freopen("1.inp","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~
Main.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen("1.out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~
Main.cpp:70:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   70 |     freopen(task".inp","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Main.cpp:71:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |     freopen(task".out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 3 / 3
• Subtask 3: 3 / 3
• Subtask 4: 3 / 3
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 4 / 4