Submission #879666

#	Time	Username	Problem	Language	Result	Execution time	Memory
879666		Giselus	Passport (JOI23_passport)	C++17	100 / 100	646 ms	116752 KiB

passport

#include<cstdio>
#include<algorithm>
#include<vector>
#include<queue>
#include<deque>
#define S 262144

using namespace std;

vector<pair<int,int>> V[4*S]; 

bool vis[4*S][3];
int dist[4*S][3];
void BFS(int x, int t){
    deque<pair<int,int>> q;
    q.push_front({x,0});
    while(!q.empty()){
        int v = q.front().first;
        int d = q.front().second;
        q.pop_front();
        if(vis[v][t])
            continue;
        vis[v][t] = 1;
        dist[v][t] = d;
        for(int i = 0; i < V[v].size(); i++){
            int u = V[v][i].first;
            int d2 = V[v][i].second;
            if(d2 == 0){
                q.push_front({u,d});
            }else{
                q.push_back({u,d+1});
            }
        }
    }
}

void addEdge(int l, int r, int ll, int rr, int w, int v){
    if(l > rr || r < ll)
        return;
    if(l >= ll && r <= rr){
        V[w].push_back({v,1});
        return;
    }
    int sr = (l+r)/2;
    addEdge(l,sr,ll,rr,w*2,v);
    addEdge(sr+1,r,ll,rr,w*2+1,v);
}

int ans[S];

int tree[4*S];

void sett(int w, int x){
    w = w+S-1;
    while(w != 0){
        tree[w] = min(tree[w], x);
        w /= 2;
    }
}

int getMin(int l, int r, int ll, int rr, int w){
    if(l > rr || r < ll)
        return 1e9;
    if(l >= ll && r <= rr){
        return tree[w];
    }
    int sr = (l+r)/2;
    return min(getMin(l,sr,ll,rr,w*2), getMin(sr+1,r,ll,rr,w*2+1));
}
int L[S];
int R[S];
int main(void){
    for(int i = 2; i < 2*S; i++){
        V[i].push_back({i/2,0});
    }
    int n;
    scanf("%d",&n);
    for(int i = 1; i <= n; i++){
        int l, r;
        scanf("%d %d",&l,&r);
        L[i] = l;
        R[i] = r;
        addEdge(1,S,l,r,1,2*S+i);
    }
    for(int i = 1; i <= n; i++){
        V[2*S+i].push_back({i+S-1,0});
    }
    BFS(2*S+1,1);
    BFS(2*S+n,2);
    dist[2*S+1][1] = 1;
    dist[2*S+n][2] = 1;
    
    for(int i = 1; i < 2*S;i++){
        tree[i] = 1e9;
    }

    vector<pair<int,int>> P;
    for(int i = 1; i <= n; i++){
        if(!vis[2*S+i][1] || !vis[2*S+i][2]){
            ans[i] = 1e9;
        }else{
            ans[i] = dist[2*S+i][1] + dist[2*S+i][2] - 1;
        }
        sett(i, ans[i]);
        if(ans[i] < 1e8)
            P.push_back({ans[i], i});
    }
    sort(P.begin(), P.end());
    for(int i = 0; i < P.size(); i++){
        int v = P[i].second;
        // printf("%d %d*\n",v,ans[v]);
        ans[v] = min(ans[v], 1 + getMin(1,S,L[v], R[v], 1));
        sett(v,ans[v]);
        // printf("%d %d$\n",v, ans[v]);
    }

    int q;
    scanf("%d", &q);
    for(int i = 1; i <= q; i++){
        int x;
        scanf("%d", &x);
        if(ans[x] >= 1e8)
            ans[x] = -1;
        printf("%d\n",ans[x]);
    }
    // for(int i = 1; i <= n; i++){
    //     printf("%d %d\n", dist[2*S+i][1], dist[2*S+i][2]);
    // }

    return 0;
}

Compilation message (stderr)

passport.cpp: In function 'void BFS(int, int)':
passport.cpp:25:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |         for(int i = 0; i < V[v].size(); i++){
      |                        ~~^~~~~~~~~~~~~
passport.cpp: In function 'int main()':
passport.cpp:109:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |     for(int i = 0; i < P.size(); i++){
      |                    ~~^~~~~~~~~~
passport.cpp:77:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   77 |     scanf("%d",&n);
      |     ~~~~~^~~~~~~~~
passport.cpp:80:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |         scanf("%d %d",&l,&r);
      |         ~~~~~^~~~~~~~~~~~~~~
passport.cpp:118:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  118 |     scanf("%d", &q);
      |     ~~~~~^~~~~~~~~~
passport.cpp:121:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  121 |         scanf("%d", &x);
      |         ~~~~~^~~~~~~~~~

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