Submission #722355

#	Time	Username	Problem	Language	Result	Execution time	Memory
722355		n0sk1ll	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	645 ms	262144 KiB

skyscraper

#include <bits/stdc++.h>

#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);cerr.tie(0)
#define mp make_pair
#define xx first
#define yy second
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define all(x) x.begin(),x.end()
#define ff(i,a,b) for (int i = a; i < b; i++)
#define fff(i,a,b) for (int i = a; i <= b; i++)
#define bff(i,a,b) for (int i = b-1; i >= a; i--)
#define bfff(i,a,b) for (int i = b; i >= a; i--)

using namespace std;
long double typedef ld;
unsigned int typedef ui;
long long int typedef li;
pair<int,int> typedef pii;
pair<li,li> typedef pli;
pair<ld,ld> typedef pld;
vector<vector<int>> typedef graph;
unsigned long long int typedef ull;
//const int mod = 998244353;
//const int mod = 1000000007;







//Note to self: Check for overflow

bool vis[30003];
vector<int> psi[30003];

int km=0; const int sf=30'003;
vector<int> dat[2*sf+15];

int main()
{
    FAST;

    int n,m; cin>>n>>m;
    set<pii> doges;

    int s,t;
    ff(i,0,m)
    {
        int b,p; cin>>b>>p;
        doges.insert({b,p});
        if (i==0) s=b;
        if (i==1) t=b;
    }

    for (auto [b,p] : doges) psi[b].pb(p);

    dat[0].pb(s);
    fff(d,0,n*1000)
    {
        if (d-km*sf>=sf)
        {
            ff(i,0,sf) swap(dat[i],dat[i+sf]);
            ff(i,0,sf) vector<int>().swap(dat[i+sf]);
            ff(i,0,2*sf) dat[i].shrink_to_fit();
            km++;
        }
        for (auto p : dat[d-km*sf])
        {
            if (vis[p]) continue; vis[p]=1;
            if (p==t) return cout<<d,0;
            for (auto jmp : psi[p])
            {
                for (int j=1;;j++)
                {
                    if (p+j*jmp>=n) break;
                    dat[d+j-km*sf].pb(p+j*jmp);
                }
                for (int j=1;;j++)
                {
                    if (p-j*jmp<0) break;
                    dat[d+j-km*sf].pb(p-j*jmp);
                }
            }
        }
        dat[d-km*sf].clear();
    }

    cout<<-1;
}

//Note to self: Check for overflow

/*

5 3
0 2
1 1
4 1

*/

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:73:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   73 |             if (vis[p]) continue; vis[p]=1;
      |             ^~
skyscraper.cpp:73:35: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   73 |             if (vis[p]) continue; vis[p]=1;
      |                                   ^~~
skyscraper.cpp:74:13: warning: 't' may be used uninitialized in this function [-Wmaybe-uninitialized]
   74 |             if (p==t) return cout<<d,0;
      |             ^~

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