Submission #106757

#	Time	Username	Problem	Language	Result	Execution time	Memory
106757		brcode	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	100 / 100	225 ms	65636 KiB

skyscraper

#include <iostream>
#include <queue>
#include <set>
#include <vector>
using namespace std;
priority_queue<pair<int,int>> q1;
const int MAXN = 30010;
set<int> v1[MAXN];
vector<pair<int,int>> g[MAXN];
bool visited[MAXN];
int dp[MAXN];
int target;

int first,jump;
int main(){
    int n,m;
    cin>>n>>m;
    for(int i=0;i<m;i++){
        int b,p;
        cin>>b>>p;
        if(i== 0){
            first = b;
            jump = p;
        }
        if(i == 1){
            target = b;
        }
        
        v1[b].insert(p);
    }
    for(int i=0;i<=n;i++){
        for(int x:v1[i]){
            
            int b = i;
            int p = x;
            int count = 1;
            for(int j=b+p;j<=n;j+=p){
               // cout<<i<<" "<<j<<endl;
                if(v1[j].find(p) != v1[j].end()){
                    g[b].push_back(make_pair(j,count));
                    break;
                }
                g[b].push_back(make_pair(j,count));
                count++;
            }
            count = 1;
            for(int j=b-p;j>=0;j-=p){
                if(v1[j].find(p) != v1[j].end()){
                    g[b].push_back(make_pair(j,count));
                    break;
                }
                g[b].push_back(make_pair(j,count));
                count++;
            }
        }
        
    }
    q1.push(make_pair(0,first));
    for(int i=0;i<=n;i++){
        dp[i] = 1e9;
    }
    dp[first] = 0;
    
    while(!q1.empty()){
        auto hold = q1.top();
        int skyscraper = hold.second;
        int dist = -1*hold.first;
       
        q1.pop();
        if(skyscraper == target){
            cout<<dist<<endl;
            return 0;
        }
        if(visited[skyscraper]){
            continue;
        }
        visited[skyscraper] = true;
        for(auto x:g[skyscraper]){
            int w = x.second;
            int to = x.first;
            if(dp[to]>dp[skyscraper]+w){
                dp[to] = dp[skyscraper]+w;
                q1.push(make_pair(-1*dp[to],to));
            }
        }
        
    }
    cout<<-1<<endl;
}

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