Submission #25162

#	Time	Username	Problem	Language	Result	Execution time	Memory
25162		kajebiii	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	159 ms	9252 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int (i)=0;(i)<(int)(n);(i)++)
#define REPO(i,n) for(int (i)=1; (i)<=(int)(n); (i)++)
#define SZ(v) ((int)(v).size())
#define ALL(v) (v).begin(),(v).end()
#define one first
#define two second
typedef long long ll;
typedef pair<int, int> pi;
const int INF = 0x3f2f1f0f;
const ll LINF = 1ll * INF * INF;

const int MAX_N = 3e4 + 100;
int N, M, St, En;
vector<int> List[MAX_N];
int main() {
	cin >> N >> M;
	REP(i, M) {
		int x, p; scanf("%d%d", &x, &p);
		if(i == 0) St = x;
		if(i == 1) En = x;
		List[x].push_back(p);
	}
	for(int i=0; i<N; i++) {
		sort(ALL(List[i]));
		List[i].erase(unique(ALL(List[i])), List[i].end());
	}

	priority_queue<pi, vector<pi>, greater<pi> > Q;
	vector<int> dis(N+1, INF);
	Q.push(pi(0, St)); dis[St] = 0;
	while(!Q.empty()) {
		int d, x; tie(d, x) = Q.top(); Q.pop();
		if(dis[x] < d) continue;
		for(int p : List[x]) {
			for(int i=x+p, cnt=1; i<N; i+=p, cnt++) {
				if(dis[i] > d+cnt)
					Q.push(pi(dis[i] = d+cnt, i));
				int ix = lower_bound(ALL(List[i]), p) - List[i].begin();
				if(ix < SZ(List[i]) && List[i][ix] == p) break;
			}
			for(int i=x-p, cnt=1; i>=0; i-=p, cnt++) {
				if(dis[i] > d+cnt)
					Q.push(pi(dis[i] = d+cnt, i));
				int ix = lower_bound(ALL(List[i]), p) - List[i].begin();
				if(ix < SZ(List[i]) && List[i][ix] == p) break;
			}
		}
	}
	if(dis[En] == INF) dis[En] = -1;
	printf("%d\n", dis[En]);
	return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:22:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   int x, p; scanf("%d%d", &x, &p);
                                  ^

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