Submission #108494

#	Time	Username	Problem	Language	Result	Execution time	Memory
108494		shashwatchandra	Money (IZhO17_money)	C++17	0 / 100	32 ms	31744 KiB

money

/*input
8
3 2 3 2 3 2 3 2
*/
#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

#define int long long 
#define double long double
#define f first
#define s second
#define mp make_pair
#define pb push_back

#define RE(i,n) for (int i = 1; i <= n; i++)
#define RED(i,n) for (int i = n; i > 0; i--)
#define REPS(i,n) for(int i = 1; (i*i) <= n; i++)
#define REP(i,n) for (int i = 0; i < (int)n; i++)
#define FOR(i,a,b) for (int i = a; i < b; i++)
#define REPD(i,n) for (int i = n-1; i >= 0; i--)
#define FORD(i,a,b) for (int i = a; i >= b; i--)

#define all(v) v.begin(),v.end()
#define pii pair<int,int>
#define vi vector<int>
#define vvi vector<vi>
#define print(arr) for (auto it = arr.begin(); it != arr.end(); ++it) cout << *it << " "; cout << endl;
#define debug(x) cout << x << endl;
#define debug2(x,y) cout << x << " " << y << endl;
#define debug3(x,y,z) cout << x << " " << y << " " << z << endl;

typedef tree<
int,
null_type,
less<int>,
rb_tree_tag,
tree_order_statistics_node_update>
ordered_set;

const int INF = 1e18+1;
const int MOD = 1e9+7;
const double PI = 3.14159265358979323846264338;

int raise(int a,int n,int m = MOD){
  if(n == 0)return 1;
  if(n == 1)return a;
  int x = 1;
    x *= raise(a,n/2,m);
    x %= m;
    x *= x;
    x %= m;
    if(n%2)x*= a;
    x %= m;
    return x;
}

int floor1(int n,int k){
    if(n%k == 0 || n >= 0)return n/k;
    return (n/k)-1;
}

int ceil1(int n,int k){
    return floor1(n+k-1,k);
}

const int N = 1e6+1;
int n;
int a[N];
int seg[4*N];
int mark[N];
bool done[N];

#define mid (l+r)/2

void add(int node,int l,int r,int ind){
     if(ind < l or ind > r)return;
     if(l == r and r == ind){
     	seg[node]++;
        return;
     }
     add(2*node,l,mid,ind);add(2*node+1,mid+1,r,ind);
     seg[node] = seg[2*node]+seg[2*node+1];
}

int query(int node,int l,int r,int start,int end){

	 if(l > end or r < start)return 0;
	 if(l >= start and r <= end)return seg[node];
	 return query(2*node,l,mid,start,end)+query(2*node+1,mid+1,r,start,end);
}

#undef mid

bool check(int i,int j){
	if(abs(a[i]-a[j]) < 2)return 1;
	if(query(1,1,N-1,a[i]+1,a[j]-1))return 0;
	return 1;
}

void solve(){
     cin >> n;
    // mark[n+1] = INF;
     REP(i,4*N)seg[i] = 0;
     RE(i,n){
     	cin >> a[i];
     	done[i] = 0;
     	if(i == 1)mark[i] = 1;
     	else{
     		mark[i] = mark[i-1]+(a[i] < a[i-1]);
     	}
     //	cout << mark[i] << " ";

     }
     //cout << endl;
     int ans = 0;
     int j = 2;
     int donetill = 0;
     RE(i,n){
       if(donetill >= i){
       	add(1,1,N-1,a[i]);
       	continue;
       }
       while(check(i,j)){
       	j++;
       	if(j == n+1)break;
       	if(mark[i] != mark[j])break;
       }
       donetill = j-1;
       //cout << i << ": " << j << endl;
       ans++;
       add(1,1,N-1,a[i]); 
     }

     cout << ans;
}

signed main(){
  ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
  //freopen(".in","r",stdin);freopen(".out","w",stdout);
  int t = 1;
  //cin >> t;
  while(t--){
    solve();
  }
  return 0;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 16
• Subtask 3: 0 / 20
• Subtask 4: 0 / 55