Submission #435347

#	Time	Username	Problem	Language	Result	Execution time	Memory
435347		iANikzad	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	415 ms	203920 KiB

skyscraper

#include<bits/stdc++.h>

using namespace std;

#define pb push_back
#define F first
#define S second
#define debug(x) cerr<<#x<<" :"<<x<<"\n"
#define all(x) x.begin(),x.end()
#define pii pair<int,int>
#define mp make_pair
#define FAST ios_base::sync_with_stdio(false), cin.tie(), cout.tie();
//#define int long long

typedef long long ll;
typedef long double ld;

const int maxn = 3e4 + 7;
const int mod = 1e9 + 7;
const int INF = 1e9 + 7;
const int mlog = 20;
const int SQRT = 170;

int n, m;
int a[maxn], p[maxn];

vector<int> vec[maxn];
vector<pii> q[maxn * SQRT];

int ss, res;

int H[maxn][SQRT], F[maxn];

void add(int x,int u,int t)
{
    if(u >= SQRT)
    {
        for(int i = 0; i < SQRT; i++)
        {
            if(x + i*u < n && !H[x+i*u][0])
                ss++, q[t+i].pb(mp(x+i*u,0));

            if(x - i*u >= 0 && !H[x-i*u][0])
                ss++, q[t+i].pb(mp(x-i*u,0));
        }
    }
    else if(!H[x][u]) ss++, q[t].pb(mp(x,u));
}



int32_t main()
{
    FAST;

    cin >> n >> m;
    for(int i = 0; i < m; i++)
    {
        cin >> a[i] >> p[i];
        vec[a[i]].pb(p[i]);
    }

    add(a[0], p[0], 0);

    for(res = 0; ss; res++)
    {
        for(int i = 0; i < q[res].size(); i++, ss--)
        {
            int x = q[res][i].F;
            int u = q[res][i].S;

            if(x == a[1]) return cout << res << "\n", 0;

            if(H[x][u]) continue;
            H[x][u] = 1;

            if(u) if(x + u < n && !H[x + u][u]) ss++ ,q[res + 1].pb(mp(x + u,u));
            if(x - u >= 0 && !H[x - u][u]) ss++, q[res + 1].pb(mp(x - u,u));

            if(F[x]) continue;
            F[x] = 1;

            for(int j = 0; j < vec[x].size(); j++)
                add(x, vec[x][j], res);
        }
    }

    cout << -1 << "\n";

    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int32_t main()':
skyscraper.cpp:67:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |         for(int i = 0; i < q[res].size(); i++, ss--)
      |                        ~~^~~~~~~~~~~~~~~
skyscraper.cpp:83:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |             for(int j = 0; j < vec[x].size(); j++)
      |                            ~~^~~~~~~~~~~~~~~

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