Submission #398419

#	Time	Username	Problem	Language	Result	Execution time	Memory
398419		tengiz05	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	1091 ms	225256 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
inline long long msb(long long val){return 63-__builtin_clzll(val);}
inline int msb(int val){return 31-__builtin_clz(val);}
//~ #define int long long
#define FASTIO ios_base::sync_with_stdio(false); cin.tie(NULL);
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define pii pair<int, int>
#define ff first
#define ss second
#define PI acos(-1)
#define ld long double
template<class T> bool chmin(T& a, const T& b) {return a>b? a=b, true:false;}
template<class T> bool chmax(T& a, const T& b) {return a<b? a=b, true:false;}
const int mod = 1e9+7, N = 30000, M = 30000;
int n, m, k;
bitset<M> used[N];
bitset<N> vis[N];
int len[N];
vector<int> who_is_here[N];
void solve(int test_case){
	int i, j;
	cin >> n >> m;
	int start;
	for(i=0;i<m;i++){
		int pos;
		cin >> pos >> len[i];
		if(i){
			who_is_here[pos].pb(i);
		}else {
			start = pos;
		}
	}
	priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>, greater<tuple<int,int,int>>> q;
	//~ deque<tuple<int,int,int>> q;
	q.emplace(0,start,0);
	used[start][0] = 1;
	vis[start][len[0]] = 1;
	while(!q.empty()){
		auto [dist, pos, i] = q.top(); q.pop();
		if(i == 1){
			cout << dist << '\n';
			return;
		}
		while(who_is_here[pos].size()){
			auto x = who_is_here[pos].back();
			who_is_here[pos].pop_back();
			if(x == 1){
				cout << dist << '\n';
				return;
			}
			if(vis[pos][len[x]])continue;
			used[pos][x] = 1;
			vis[pos][len[x]] = 1;
			q.emplace(dist,pos,x);
		}
		for(int p=pos-len[i],d=dist+1;p>=0;p-=len[i],d++){
			if(!used[p][i] && !vis[p][len[i]]){
				used[p][i] = 1;
				vis[p][len[i]] = 1;
				q.emplace(d,p,i);
			}
		}
		for(int p=pos+len[i],d=dist+1;p<n;p+=len[i],d++){
			if(!used[p][i] && !vis[p][len[i]]){
				used[p][i] = 1;
				vis[p][len[i]] = 1;
				q.emplace(d,p,i);
			}
		}
	}
	cout << -1 << '\n';
	return;
}

signed main(){
	FASTIO;
//~ #define MULTITEST 1
#if MULTITEST
	int _T;
	cin >> _T;
	for(int T_CASE = 1; T_CASE <= _T; T_CASE++)
		solve(T_CASE);
#else
	solve(1);
#endif
	return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'void solve(int)':
skyscraper.cpp:23:9: warning: unused variable 'j' [-Wunused-variable]
   23 |  int i, j;
      |         ^
skyscraper.cpp:25:6: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
   25 |  int start;
      |      ^~~~~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 14 / 14
• Subtask 4: 21 / 21
• Subtask 5: 0 / 43