Submission #41517

#	Time	Username	Problem	Language	Result	Execution time	Memory
41517		wzy	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	342 ms	153100 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
vector<pii> adj[300005];
int  n, m;
set<int> p[300005];
long long d[300005];

int32_t main(){
	scanf("%lld%lld" ,  &n,  &m);
	int target = -1;
	int start = 0;
	for(int i = 0 ; i <m ; i ++){
		int  b, x;
		scanf("%lld%lld" , &b , &x);
		p[b].insert(x);
		if(i == 1){
			target = b;
		}
		if(i == 0){
			start = b;
		}
	}
	for(int i = 0 ; i < n; i++){
		for(auto t : p[i]){
			for(int j = 1  ; j*t + i < n ; j++){
				adj[i].pb(pii(j , j*t+i));
				if(p[j*t + i].count(t)) break;
			}
			for(int j = 1 ; i - j*t >=0 ; j++){
				adj[i].pb(pii(j , i-j*t));
				if(p[i - j*t].count(t)) break;
			}	
		}
	}
	priority_queue<pii , vector<pii> , greater<pii> > pq;
	pq.push(pii(0 , start));
	for(int i = 0 ; i< n; i++) d[i] = (long long) 1e18;
	d[start] = 0;
	while(!pq.empty()){
		pii u = pq.top();
		pq.pop();
		if(d[u.S] < u.F) continue;
		for(int i = 0 ; i < adj[u.S].size() ; i++){
			pii v = adj[u.S][i];
			if(d[v.S] > u.F + v.F){
				d[v.S] = u.F + v.F;
				pq.push(pii(u.F + v.F , v.S));
			}
		}
	}
	if(target == -1) printf("%lld\n" , -1LL);
	else{
	if(d[target] == (int) 1e18) printf("%lld\n" , -1LL);
	else{
		printf("%lld\n" , d[target]);
	}
}
}

Compilation message (stderr)

skyscraper.cpp: In function 'int32_t main()':
skyscraper.cpp:49:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0 ; i < adj[u.S].size() ; i++){
                     ^
skyscraper.cpp:15:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%lld%lld" ,  &n,  &m);
                              ^
skyscraper.cpp:20:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lld%lld" , &b , &x);
                              ^

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