Submission #660799

#	Time	Username	Problem	Language	Result	Execution time	Memory
660799		velislavgarkov	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	36 / 100	315 ms	262144 KiB

skyscraper

#include <iostream>
#include <vector>
#include <queue>
using namespace std;
const int MAXN=3e4+10;
vector <pair <int,int> > v[MAXN];
priority_queue <pair <int,int> > q;
int ans[MAXN];
void dejkstra(int start) {
    ans[start]=0;
    q.push({0,start});
    while (!q.empty()) {
        int x=q.top().second;
        if (-q.top().first!=ans[x]) {
            q.pop();
            continue;
        }
        q.pop();
        for (auto i:v[x]) {
            if (ans[i.first]==-1 || ans[i.first]>ans[x]+i.second) {
                ans[i.first]=ans[x]+i.second;
                q.push({-ans[i.first],i.first});
            }
        }
    }
}
int main () {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n, m, beg, steps, start, ed;
    cin >> n >> m;
    for (int j=0;j<m;j++) {
        cin >> beg >> steps;
        if (j==0) start=beg;
        if (j==1) ed=beg;
        int br=1;
        for (int i=beg+steps;i<n;i+=steps) {
            v[beg].push_back({i,br});
            br++;
        }
        br=1;
        for (int i=beg-steps;i>=0;i-=steps) {
            v[beg].push_back({i,br});
            br++;
        }
    }
    for (int i=0;i<n;i++) ans[i]=-1;
    dejkstra(start);
    cout << ans[ed] << endl;
    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:50:19: warning: 'ed' may be used uninitialized in this function [-Wmaybe-uninitialized]
   50 |     cout << ans[ed] << endl;
      |                   ^
skyscraper.cpp:49:13: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
   49 |     dejkstra(start);
      |     ~~~~~~~~^~~~~~~

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