Submission #877871

#	Time	Username	Problem	Language	Result	Execution time	Memory
877871		sysia	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	57 / 100	194 ms	262144 KiB

skyscraper

//Sylwia Sapkowska
#include <bits/stdc++.h>
#pragma GCC optimize("O3", "unroll-loops")
using namespace std;

void __print(int x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << "'" << x << "'";}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}

template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ", "; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? ", " : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifdef LOCAL
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif

#define int long long
typedef pair<int, int> T;
const int oo = 1e18, oo2 = 1e9+7, K = 30;
const int mod = 998244353;

// const int s = 770;
// #warning ch s
// const int s = 3;

void solve(){
    int n, m; cin >> n >> m;
    int s = n;
    vector<vector<T>>g(n*s+2);
    
    auto ch = [&](int v, int j = 0){
        return v*s+j;
    };
    int ile = 0;
    auto add_edge = [&](int a, int b, int c, bool two = 0){
        if (two) g[a].emplace_back(b, c);
        g[b].emplace_back(a, c);
        ile++;
        // cout << a << " " << b << " " << c << "\n";
    };
    set<T>was;
    int start, kon;
    for (int i = 0; i<m; i++){
        int v, j; cin >> v >> j;
        if (i == 0) start = v;
        if (i == 1) kon = v;
        if (j >= n) continue;
        // if (j < s){
            if (was.find({v%j, j}) == was.end()){
                debug(v, j);
                was.insert({v%j, j});
                int u = v;
                add_edge(ch(u), ch(u, j), 0);
                while (u >= j){
                    add_edge(ch(u-j), ch(u-j, j), 0);
                    add_edge(ch(u, j), ch(u-j, j), 1, 1);
                    u-=j;
                }
                u = v;
                while (u + j < n){
                    add_edge(ch(u+j), ch(u+j, j), 0);
                    add_edge(ch(u, j), ch(u+j, j), 1, 1);
                    u += j;
                }
            }
            add_edge(ch(v, j), ch(v), 0);
        // } else {
        //     int u = v;
        //     while (u >= j){
        //         add_edge(ch(u), ch(u-j), 1, 1);
        //         u-=j;
        //     }
        //     u = v;
        //     while (u + j < n){
        //         add_edge(ch(u), ch(u+j), 1, 1);
        //         u += j;
        //     }
        // }
    }
    deque<int>q;
    vector<int>dist(n*s+2, oo);
    q.push_back(ch(start));
    dist[ch(start)] = 0;
    while ((int)q.size()){
        int v = q.front(); q.pop_front();
        for (auto [x, c]: g[v]){
            if (dist[x] == oo){
                dist[x] = dist[v] + c;
                if (!c) q.push_front(x);
                else q.push_back(x);
            }
        }
    }
    int ans = dist[ch(kon)];
    if (ans == oo) ans = -1;
    cout << ans << "\n";
}

int32_t main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t = 1;
    //cin >> t;
    while (t--) solve();

    return 0;
}

Compilation message (stderr)

skyscraper.cpp: In function 'void solve()':
skyscraper.cpp:42:17: warning: 'kon' may be used uninitialized in this function [-Wmaybe-uninitialized]
   42 |         return v*s+j;
      |                ~^~
skyscraper.cpp:42:17: warning: 'start' may be used uninitialized in this function [-Wmaybe-uninitialized]
   42 |         return v*s+j;
      |                ~^~

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