Submission #1254127

#	Time	Username	Problem	Language	Result	Execution time	Memory
1254127		VKhang	Jakarta Skyscrapers (APIO15_skyscraper)	C++20	10 / 100	20 ms	28080 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
const int N = 1e6 + 5, MOD = 1e9 + 7;
const long long L = 1e18;
#define ll long long
#define fi first
#define se second
#define yes {cout << "YES";return;}
#define no  {cout << "NO"; return;}
#define pb push_back
#define MASK(i) (1ll << (i))
#define BIT(i, s) ((1ll << (i)) & (s))
#define all(a) a.begin(), a.end()
int n, m;
int a[N], b[N];
bool visited[N];
int dist[N];
vector <int> s[N];
priority_queue <pair <int, int>, vector<pair <int, int>>, greater <pair <int, int>>> p;
bool Left[N], Right[N];
void solve()
{
    cin >> n >> m;
    for (int i = 0; i < m; i++){
        cin >> a[i] >> b[i];
        s[a[i]].pb(i);
    }
    memset(dist, 0x3f, sizeof dist);
    dist[0] = 0;
    p.push({0, 0});
    while(p.size()){
        int i = p.top().fi;
        int j = p.top().se;
        p.pop();
        if (visited[j]) continue;
        visited[j] = true;
        bool ok = true;
        for (int l = a[j]; ok && l >= 0; l -= b[j]){
            for (int x: s[l]){
                if (x == j || visited[x] || dist[x] == i) continue;
                int y = (a[j] - l) / b[j];
                dist[x] = min(dist[x], i + y);
                if (b[x] == b[j]) ok = false;
                p.push({dist[x], x});
            }
        }
       ok = true;
        for (int l = a[j]; ok && l < n; l += b[j]){
            for (int x: s[l]){
                if (visited[x] || dist[x] == i) continue;
                int y = (l - a[j]) / b[j];
                dist[x] = min(dist[x], i + y);
                if (b[x] == b[j]) ok = false;
                p.push({dist[x], x});
            }
        }
    }
    cout << (dist[1] == dist[n + 1] ? -1 : dist[1]);
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    if (fopen("VKhang.inp","r")){
        freopen("VKhang.inp","r",stdin);
        freopen("VKhang.out","w",stdout);
    }
    solve();
    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:64:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |         freopen("VKhang.inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:65:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |         freopen("VKhang.out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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