Submission #925649

#	Time	Username	Problem	Language	Result	Execution time	Memory
925649		Baizho	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	185 ms	63308 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
  
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
 
 #pragma GCC optimize("Ofast,unroll-loops,fast-math")
 #pragma GCC target("popcnt")
 
 
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> pll;
 
#define sz size()
#define ff first
#define ss second
#define all(a) a.begin(),a.end()
#define pb push_back
 
const int mod = ll(1e9)+7; //(b + (a%b)) % b (to mod -1%(10^9+7) correctly in c++ its -1 but its suppose to be 10^9+6
const ll MOD = 998244353;  // (a%mod)*(binpow(b,mod-2,mod) = (a/b)%mod
const int N = ll(3e4)+100;
const int M = ll(2e5) + 100;
const long long inf = 5e18;
const long double eps = 1e-15L;
 
ll lcm(ll a, ll b) { return (a / __gcd(a,b))*b; }
 
ll binpow(ll a, ll b, ll m) { ll res=1; a %= m; while(b>0){ if(b&1)res=(res * a) % m; a=(a * a) % m; b/=2; } return res%m;}
 
void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }

int n, m, dis[N], b[N];
vector<pair<int, int> > g[N];
set<int> po[N];

void Baizho() {
	cin>>n>>m;
	for(int i = 0; i < m; i ++) {
		int p; cin>>b[i]>>p;
		po[b[i]].insert(p);
	}
	for(int i = 0; i < n; i ++) {
		for(auto p : po[i]) {
			int pos = i + p, cur = 1;
			while(pos < n) {
				g[i].pb({pos, cur});
				if(po[pos].find(p) != po[pos].end()) break;
				pos += p; cur += 1;
			}
			pos = i - p, cur = 1;
			while(pos >= 0) {
				g[i].pb({pos, cur});
				if(po[pos].find(p) != po[pos].end()) break;
				pos -= p; cur += 1;
			}
		}
	}
	for(int i = 0; i <= n; i ++) dis[i] = 1e9;
	dis[b[0]] = 0;
	set<pair<int, int> > st;
	st.insert({dis[b[0]], b[0]});
	while(!st.empty()) {
		int v = (*st.begin()).ss;
		st.erase(st.begin());
		for(auto got: g[v]) {
			int to = got.ff, w = got.ss;
			if(dis[to] > dis[v] + w) {
				if(dis[to] != 1e9) st.erase({dis[to], to});
				dis[to] = dis[v] + w;
				st.insert({dis[to], to});
			}
		}
	}
	if(dis[b[1]] == 1e9) dis[b[1]] = -1;
	cout<<dis[b[1]];
}
 
signed main() {		
// 	Freopen("nondec");
    ios_base::sync_with_stdio(false);   
    cin.tie(0);cout.tie(0); 
//   	precalc();
   	
    int ttt = 1;
//    cin>>ttt;
 
    for(int i=1; i<=ttt; i++) {Baizho(); }
}

Compilation message (stderr)

skyscraper.cpp: In function 'void Freopen(std::string)':
skyscraper.cpp:35:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 | void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                           ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:35:76: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 | void Freopen(string Key){ freopen((Key+".in").c_str(), "r", stdin); freopen((Key+".out").c_str(), "w", stdout); }
      |                                                                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 43 / 43