Submission #791201

#	Time	Username	Problem	Language	Result	Execution time	Memory
791201		ThMinh_	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	57 / 100	1054 ms	57464 KiB

skyscraper

#include<bits/stdc++.h>
#define forin(i, a, b) for(int i = a; i <= b; ++i)
#define ii pair<int, int>
#define iii pair<int, ii>
using namespace std;
const int N = 3e4 + 10, T = 180;
int n, m, inf;
int b[N], p[N], d[T + 10][N];
vector<int> walk[N];
vector<ii> tele[N];
priority_queue<iii, vector<iii>, greater<iii> > pq;
int main () {
    cin.tie(0)->sync_with_stdio(0);
    if(fopen("Task.inp","r")) {
        freopen("Task.inp","r",stdin);
        freopen("WA.out","w",stdout);
    }
    cin>>n>>m;
    int s = sqrt(n);
    forin(i, 1, m) {
        cin>>b[i]>>p[i];
        if(p[i] > s) {
            int pos = b[i], d = 0;
            do {
                if(d) tele[b[i]].push_back({pos, d});
                pos += p[i];
                d++;
            } while(pos < n);
            pos = b[i]; d = 0;
            do {
                if(d) tele[b[i]].push_back({pos, d});
                pos -= p[i];
                d++;
            } while(pos >= 0);
        }
        else walk[b[i]].push_back(p[i]);
    }
    memset(d, 60, sizeof(d));
    inf = d[0][0];
    d[0][b[1]] = 0;
    pq.push({0, {b[1], 0}});
    while(!pq.empty()) {
        int kc = pq.top().first;
        int u, l; tie(u, l) = pq.top().second;
        pq.pop();
        if(d[l][u] != kc) continue;
        if(l) walk[u].push_back(l);
        for(auto e : tele[u]) {
            int v, w; tie(v, w) = e;
            if(d[0][v] <= kc + w) continue;
            d[0][v] = kc + w;
            pq.push({d[0][v], {v, 0}});
        }
        for(auto w : walk[u]) {
            if(u - w >= 0) {
                if(d[w][u - w] <= kc + 1) continue;
                d[w][u - w] = kc + 1;
                pq.push({d[w][u - w], {u - w, w}});
            }
        }
        for(auto w : walk[u]) {
            if(u + w < n) {
                if(d[w][u + w] <= kc + 1) continue;
                d[w][u + w] = kc + 1;
                pq.push({d[w][u + w], {u + w, w}});
            }
        }
        if(l) walk[u].pop_back();
    }
    int ans = inf;
    forin(i, 0, T) ans = min(ans, d[i][b[2]]);
    if(ans == inf) cout<<-1;
    else cout<<ans;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:15:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |         freopen("Task.inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:16:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |         freopen("WA.out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~

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