Submission #133543

#	Time	Username	Problem	Language	Result	Execution time	Memory
133543		junodeveloper	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	291 ms	68196 KiB

skyscraper

#include <bits/stdc++.h>
#define sz(x) ((int)x.size())
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pi;
int n,m;
int B[30010],P[30010],D[30010];
set<int> ps[30010];
vector<pi> adj[30010];
int main() {
	scanf("%d%d",&n,&m);
	int i,j;
	for(i=0;i<m;i++) {
		scanf("%d%d", B+i, P+i);
		ps[B[i]].insert(P[i]);
	}
	for(i=0;i<n;i++) {
		int cur;
		for(auto& it:ps[i]) {
			cur=i-it;
			while(cur>=0) {
				adj[i].push_back({cur,(i-cur)/it});
				if(ps[cur].find(it)!=ps[cur].end()) break;
				cur-=it;
			}
			cur=i+it;
			while(cur<n) {
				adj[i].push_back({cur,(cur-i)/it});
				if(ps[cur].find(it)!=ps[cur].end()) break;
				cur+=it;
			}
		}
	}
	fill(D,D+n,(int)1e9);
	priority_queue<pi,vector<pi>,greater<pi> > pq;
	pq.push({0,B[0]}); D[B[0]]=0;
	while(!pq.empty()) {
		int w,u; tie(w,u)=pq.top(); pq.pop();
		if(D[u]<w) continue;
		if(u==B[1]) break;
		for(auto& it:adj[u]) {
			if(w+it.se<D[it.fi]) {
				D[it.fi]=w+it.se;
				pq.push({D[it.fi],it.fi});
			}
		}
	}
	printf("%d\n", D[B[1]]==(int)1e9?-1:D[B[1]]);
	return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:16:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j;
        ^
skyscraper.cpp:15:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
skyscraper.cpp:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d", B+i, P+i);
   ~~~~~^~~~~~~~~~~~~~~~~~

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