Submission #699250

#	Time	Username	Problem	Language	Result	Execution time	Memory
699250		nguyentunglam	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	1089 ms	86852 KiB

skyscraper

#include<bits/stdc++.h>
#define fi first
#define se second
#define endl "\n"
#define ii pair<int, int>
using namespace std;
const int N = 3e4 + 10, M = 8e6 + 10;
unordered_map<int, int> dd;
vector<int> lst[N];
int d[M];
int cnt;
bool mark[N];
int id(int x, int y) {
    int code = x * (3e4 + 1) + y;
    if (!dd[code]) dd[code] = ++cnt;
    return dd[code];
}
int main() {
    #define task ""
    cin.tie(0) -> sync_with_stdio(0);
    if (fopen ("task.inp", "r")) {
        freopen ("task.inp", "r", stdin);
        freopen ("task.out", "w", stdout);
    }
    if (fopen (task".inp", "r")) {
        freopen (task".inp", "r", stdin);
        freopen (task".out", "w", stdout);
    }
    int n, m; cin >> n >> m;
    pair<int, int> st, ed;
    for(int i = 0; i < m; i++) {
        int b, p; cin >> b >> p;
        lst[b].push_back(p);
        if (i == 0) st = make_pair(b, p);
        if (i == 1) ed = make_pair(b, p);
    }
    deque<pair<int, int> > dq;
    d[id(st.fi, st.se)] = 1; dq.push_back(st);

    while (!dq.empty()) {
        auto [pos, jump] = dq.front(); dq.pop_front();
        int cur = id(pos, jump);
        if (!mark[pos]) {
            for(auto &j : lst[pos]) {
                int code = id(pos, j);
                if (!d[code]) d[code] = d[cur], dq.push_front({pos, j});
            }
            mark[pos] = 1;
        }
        if (pos + jump < n) {
            int code = id(pos + jump, jump);
            if (!d[code]) d[code] = d[cur] + 1, dq.push_back({pos + jump, jump});
        }
        if (pos - jump >= 0) {
            int code = id(pos - jump, jump);
            if (!d[code]) d[code] = d[cur] + 1, dq.push_back({pos - jump, jump});
        }
    }
    cout << d[id(ed.fi, ed.se)] - 1;
}

Compilation message (stderr)

skyscraper.cpp: In function 'int main()':
skyscraper.cpp:22:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |         freopen ("task.inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:23:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |         freopen ("task.out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:26:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |         freopen (task".inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:27:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |         freopen (task".out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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