Submission #888862

#	Time	Username	Problem	Language	Result	Execution time	Memory
888862		vjudge1	Passport (JOI23_passport)	C++17	22 / 100	2056 ms	57020 KiB

passport

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimize("Ofast,unroll-loops")
#define pii pair<int,int>
using namespace __gnu_pbds;
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
#define f first
#define s second
#define pii pair<int,int>
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
	tree_order_statistics_node_update> ordered_set;
const int mod= 1e9 +7;
const int N=2505;

int binpow (int a, int n) {
	if (n == 0)
		return 1;
	if (n % 2 == 1)
		return binpow (a, n-1) * a;
	else {
		int b = binpow (a, n/2);
		return b * b;
	}
}

vector<vector<int>> dist(N, vector<int> (N, mod));

void solve(){
	int n,m,k;

	cin>>n;
	
	if(n<=2505){
	vector<int>l(n+1),r(n+1);
	
	for(int i = 0;i<n;i++){
		int a,b;
		cin>>l[i]>>r[i];
		l[i]--;r[i]--;
	}
	
	int h,x;
	cin>>h>>x;
	x--;
	queue<pii>q;
	q.push({l[x],r[x]});
	dist[l[x]][r[x]] = 1;
	
	while(!q.empty()){
		auto [x,y] = q.front();
		q.pop();
		
		for(int i = x;i<=y;i++){
			int mxl = min(x,l[i]),mxr = max(r[i],y);
			if(umin(dist[mxl][mxr],dist[x][y] + 1)){
				q.push({mxl,mxr});
			}
		}
	}
	
	if(dist[0][n-1]==mod)cout<<-1<<"\n";
	else cout<<dist[0][n-1]<<"\n";
	
		
	}
	else{
		vector<pii>v;vector<int>pref(n+1,0);
	int r1 = 1;
	int cnt = 1;
	for(int i = 0;i<n;i++){
		int l,r;
		cin>>l>>r;
		v.pb({l,r});
		if(i==0)r1 = r;
		if(i==n)cout<<"Baiysh want a rulet!!!!!!!!!!!!!!!!!!!!!!\n";
		else{
			pref[i+1] = max(pref[i],r);
		}
	}
	int last = -1;int ans = 1;
	while(r1!=n){
		last = r1;
		r1 = pref[r1];
		ans++;
		if(last==r1){
			cout<<-1<<"\n";
			exit(0);
		}
	}
	cout<<ans<<"\n";
	}
	






}

 signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int cnt=0;
	int tt=1;
	while(tt--)solve();

}

Compilation message (stderr)

passport.cpp: In function 'void solve()':
passport.cpp:45:7: warning: unused variable 'a' [-Wunused-variable]
   45 |   int a,b;
      |       ^
passport.cpp:45:9: warning: unused variable 'b' [-Wunused-variable]
   45 |   int a,b;
      |         ^
passport.cpp:77:6: warning: unused variable 'cnt' [-Wunused-variable]
   77 |  int cnt = 1;
      |      ^~~
passport.cpp:37:8: warning: unused variable 'm' [-Wunused-variable]
   37 |  int n,m,k;
      |        ^
passport.cpp:37:10: warning: unused variable 'k' [-Wunused-variable]
   37 |  int n,m,k;
      |          ^
passport.cpp: In function 'int main()':
passport.cpp:114:6: warning: unused variable 'cnt' [-Wunused-variable]
  114 |  int cnt=0;
      |      ^~~

• Subtask 1: 6 / 6
• Subtask 2: 16 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 8
• Subtask 5: 0 / 46