Submission #857784

#	Time	Username	Problem	Language	Result	Execution time	Memory
857784		12345678	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	100 / 100	990 ms	66140 KiB

skyscraper

#include <bits/stdc++.h>

using namespace std;

const int nx=3e4+5, tx=180;

int n, m, st, ed, s[nx], p[nx], dp[tx][nx], dp2[nx][2*tx];
vector<int> v[nx];
priority_queue<tuple<int, int, int, int>, vector<tuple<int, int, int, int>>, greater<tuple<int, int, int, int>>> q;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n>>m>>s[0]>>p[0]>>s[1]>>p[1]; v[s[1]].push_back(1);
    for (int i=1; i<m-1; i++) cin>>s[i+1]>>p[i+1], v[s[i+1]].push_back(i+1);
    for (int i=0; i<tx; i++) for (int j=0; j<nx; j++) dp[i][j]=INT_MAX;
    for (int i=0; i<nx; i++) for (int j=0; j<2*tx; j++) dp2[i][j]=INT_MAX;
    int t=sqrt(n);
    if (p[0]>=t) dp2[0][tx]=0;
    else dp[p[0]][s[0]]=0;
    q.push({0, p[0], s[0], 0});
    while (!q.empty())
    {
        auto [w, c, l, idx]=q.top();
        //printf("%d %d %d %d\n", w, c, l, idx);
        q.pop();
        if (c>=t)
        {
            if (l+c<n&&w+1<dp2[idx][(l+c-s[idx])/p[idx]+tx]) dp2[idx][(l+c-s[idx])/p[idx]+tx]=w+1, q.push({w+1, c, l+c, idx});
            if (l-c>=0&&w+1<dp2[idx][(l-c-s[idx])/p[idx]+tx]) dp2[idx][(l-c-s[idx])/p[idx]+tx]=w+1, q.push({w+1, c, l-c, idx});
        }
        else
        {
            if (l+c<n&&w+1<dp[c][l+c]) dp[c][l+c]=w+1, q.push({w+1, c, l+c, idx});
            if (l-c>=0&&w+1<dp[c][l-c]) dp[c][l-c]=w+1, q.push({w+1, c, l-c, idx});
        }
        for (auto nw:v[l])
        {
            if (nw==1)
            {
                cout<<w;
                return 0;
            }
            if (p[nw]>=t&&w<dp2[nw][tx]) dp2[nw][tx]=w, q.push({w, p[nw], l, nw});
            if (p[nw]<t&&w<dp[p[nw]][l]) dp[p[nw]][l]=w, q.push({w, p[nw], l, nw});
        }
    }
    cout<<-1;
}

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