Submission #549747

#	Time	Username	Problem	Language	Result	Execution time	Memory
549747		Soul234	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	838 ms	7620 KiB

skyscraper

#include<bits/stdc++.h>
using namespace std;

void DBG() { cerr << "]\n"; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << h; if(sizeof...(t)) cerr << ", ";
    DBG(t...);
}
#ifdef LOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif // LOCAL

#define FOR(i,a,b) for(int i = (a) ; i<(b) ; i++)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for(int i = (b)-1 ; i>=(a) ; i--)
#define R0F(i,a) ROF(i,0,a)
#define each(e,a) for(auto &e : (a))
#define sz(v) (int)(v).size()
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
#define tcT template<class T
#define nl "\n"

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using str = string;
tcT> using V = vector<T>;
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;

void setIO(string NAME = "") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(NAME)) {
        freopen((NAME + ".inp").c_str(),"r",stdin);
        freopen((NAME + ".out").c_str(),"w",stdout);
    }
}

tcT> bool ckmin(T&a, const T&b) {
    return b < a ? a = b, 1 : 0;
}
const int MOD = 1e9+7;
const int MX = 3e4+5;
int N, M, s, t, dist[MX];
set<int> pwrs[MX];

void solve() {
    memset(dist,0x3f,sizeof dist);
    cin>>N>>M;
    F0R(i,M) {
        int b, p;
        cin>>b>>p;
        if(i==0) s = b;
        if(i==1) t = b;
        pwrs[b].insert(p);
    }
    pqg<pi> pq;
    pq.push({dist[s] = 0, s});
    while(sz(pq)) {
        int du = pq.top().first, u = pq.top().second;
        pq.pop();
        if(du != dist[u]) continue;
        each(p, pwrs[u]) {
            for(int i = 1; u-p*i>=0; i++) if(ckmin(dist[u-p*i], dist[u] + i)) pq.push({dist[u-p*i], u-p*i});
            for(int i = 1; u+p*i<N; i++) if(ckmin(dist[u+p*i], dist[u] + i)) pq.push({dist[u+p*i], u+p*i});
        }
    }
    if(dist[t] >= MOD) return void(cout<<"-1\n");
    cout << dist[t] << nl;
}

int main() {
    setIO();

    int t=1;
    //cin>>t;
    while(t-->0) {
        solve();
    }

    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'void setIO(std::string)':
skyscraper.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen((NAME + ".inp").c_str(),"r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen((NAME + ".out").c_str(),"w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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