Submission #1097348

#	Time	Username	Problem	Language	Result	Execution time	Memory
1097348		vjudge1	Passport (JOI23_passport)	C++17	0 / 100	276 ms	65820 KiB

passport

#include <iostream>
#include <cstring>
#include <vector>
#include <queue>

using namespace std;

const int INF = 1e9+7;
const int MAXN = 2e5+3;

int n, q, x;

vector<pair<int,int>> e[4*MAXN];

int ans;
int f[4*MAXN];
int ID[MAXN];
bool vis[4*MAXN];

void STbuild(int idx=1, int l=1, int r=n){
    if(l==r){
        ID[l] = idx;
        return;
    }
    int mid = l+r>>1;
    e[idx].push_back({idx<<1, 0});
    e[idx].push_back({idx<<1|1, 0});
    STbuild(idx<<1, l, mid);
    STbuild(idx<<1|1, mid+1, r);
}

void STunion(int z, int u, int v, int idx=1, int l=1, int r=n){
    if(v<l || r<u)return;
    if(u<=l && r<=v){
        if(idx==ID[z])return;
        e[ID[z]].push_back({idx, 1});
        return;
    }
    int mid = l+r>>1;
    STunion(z,u,v,idx<<1,l,mid);
    STunion(z,u,v,idx<<1|1,mid+1,r);
}



struct sub4
{
    class Compare{
    public: bool operator()(const int &a, const int &b){
        return f[a] > f[b];
    }};
    priority_queue<int, vector<int>, Compare> pq;

    void solve(){
        for(int i=1; i<=4*n; ++i) f[i] = INF, vis[i] = 0;

        pq.push(ID[x]);
        f[ID[x]] = 0;
        vis[ID[x]] = 1;

        while(!pq.empty()){
            int u = pq.top(); pq.pop();
            for(pair<int,int> &z : e[u]){
                int v = z.first,
                    w = z.second;
                if(vis[v])continue;

                pq.push(v);
                vis[v] = 1;
                f[v] = min(f[v],f[u]+w);
            }
        }
        ans = 0;
        for(int i=1; i<=n; ++i)ans=max(ans,f[ID[i]]);
        cout << (ans>=INF ? -1 : ans) << '\n';
    }
};



signed main()
{
    // cin.tie(0) -> sync_with_stdio(0);
    if(fopen("*.inp", "r")){
        freopen("*.inp", "r",stdin);
        freopen("*.out", "w",stdout);
    }
    cin >> n;
    STbuild();
    for(int l, r, i=1; i<=n; ++i){
        cin >> l >> r;
        STunion(i, l, r);
    }
    auto subans = (new sub4());
    cin >> q;
    while(q--){
        cin >> x;
        subans -> solve();
    }

    return 0;
}

Compilation message (stderr)

passport.cpp: In function 'void STbuild(int, int, int)':
passport.cpp:25:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   25 |     int mid = l+r>>1;
      |               ~^~
passport.cpp: In function 'void STunion(int, int, int, int, int, int)':
passport.cpp:39:16: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   39 |     int mid = l+r>>1;
      |               ~^~
passport.cpp: In function 'int main()':
passport.cpp:85:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   85 |         freopen("*.inp", "r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
passport.cpp:86:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |         freopen("*.out", "w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 8
• Subtask 5: 0 / 46