Submission #1110693

#	Time	Username	Problem	Language	Result	Execution time	Memory
1110693		haru09	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	139 ms	47160 KiB

skyscraper

#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second

const int ar = 5e4 + 5;
const ll mod = 1e9 + 7;

int n, m;
int sqr;
int b[ar];
int p[ar];
int dp[ar][226];
vector<int> ad[ar];
struct seg
{
    int dis, i, p;
};
bool operator>(seg a, seg b)
{
    return a.dis > b.dis;
}
queue<seg> pq;
int ans = 1e9;
void dijkstra()
{
    memset(dp, 0x3f, sizeof dp);
    pq.push({0, b[0], 0});
    dp[b[0]][0] = 0;
    while(pq.size())
    {
        seg top = pq.front();
        pq.pop();
        int dis = top.dis;
        int i = top.i;
        int pk = top.p;
        if (dp[i][pk] < dis) continue;
        if (i == b[1]) ans = min(ans, dis);
        if (pk == 0)
        {
            for (auto x : ad[i])
            {
                if (p[x] <= sqr)
                {
                    if (dp[i][p[x]] > dis)
                    {
                        dp[i][p[x]] = dis;
                        pq.push({dis, i, p[x]});
                    }
                }
                else
                {
                    int cnt = 0;
                    for (int j = i; j < n; j += p[x])
                    {
                        if (dp[j][0] > dis + cnt)
                        {
                            dp[j][0] = dis + cnt;
                            pq.push({dp[j][0], j, 0});
                        }
                        cnt++;
                    }
                    cnt = 0;
                    for (int j = i; j >= 0; j -= p[x])
                    {
                        if (dp[j][0] > dis + cnt)
                        {
                            dp[j][0] = dis + cnt;
                            pq.push({dp[j][0], j, 0});
                        }
                        cnt++;
                    }
                }
            }
        }
        else
        {
            if (i + pk < n && dp[i + pk][pk] > dis + 1)
            {
                dp[i + pk][pk] = dis + 1;
                pq.push({dp[i + pk][pk], i + pk, pk});
            }
            if (i - pk >= 0 && dp[i - pk][pk] > dis + 1)
            {
                dp[i - pk][pk] = dis + 1;
                pq.push({dp[i - pk][pk], i - pk, pk});
            }
            if (dp[i][0] > dis)
            {
                dp[i][0] = dis;
                pq.push({dp[i][0], i, 0});
            }
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m;
    for (int i = 0; i < m; i++)
    {
        cin >> b[i] >> p[i];
        ad[b[i]].push_back(i);
    }
    sqr = 225;
    dijkstra();
    if (ans == 1e9) ans = -1;
    cout << ans;
}

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