Submission #838127

#	Time	Username	Problem	Language	Result	Execution time	Memory
838127		8pete8	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	0 / 100	62 ms	131860 KiB

skyscraper

#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<limits.h>
#include<cmath>
#include<set>
#include<algorithm>
#include<bitset>
using namespace std;
#define ll long long
#define f first
#define endl "\n"
#define s second
#define pii pair<int,int>
#define ppii pair<int,pii>
#define pb push_back
#define all(x) x.begin(),x.end()
#define F(n) for(int i=0;i<n;i++)
#define lb lower_bound
#define p push
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
using namespace std;
const int mxn=3*1e4,mod=998244353,lg=42,root=80;
void setIO(string name) {
	ios_base::sync_with_stdio(0); cin.tie(0);
	freopen((name+".in").c_str(),"r",stdin);
	freopen((name+".out").c_str(),"w",stdout);
}
int dist[(2*mxn*root)+10];
vector<pii>adj[(2*mxn*root)+10];
bitset<(2*mxn*root)+10>vis;
int n,m;
//make dummy node
// n orginal + n node for each root(n)
//node more than root id = mxn*ith+starting point
void init(){
    for(int i=1;i<root;i++){
        for(int j=0;j<n;j++)adj[(mxn*i)+j].pb({j,0});//going down
    }
    for(int i=1;i<root;i++){
        for(int j=i;j<n;j+=i){
            //buid=ld edge for each i
            adj[(mxn*i)+j].pb({(mxn*i)+j-i,1});
            adj[(mxn*i)+j-i].pb({(mxn*i)+j,1});
        }
    }
}
int32_t main(){
    fastio
    cin>>n>>m;
    int cnt=0;
    init();
    for(int i=0;i<=mxn*root*2;i++)dist[i]=1e8;
    for(int i=0;i<m;i++){
        int st,p;cin>>st>>p;
        if(p<=root)adj[st].pb({(p*mxn)+st,0});
        else{
            for(int j=st;j+p<n;j+=p){
                adj[j].pb({j+p,1});
                adj[j+p].pb({j,1});
            }
            for(int j=st;j-p>=0;j-=p){
                adj[j].pb({j-p,1});
                adj[j-p].pb({j,1});
            }
            //connect normal edge
        }
        //input
    }
    //dijkstra
    priority_queue<pii,vector<pii>,greater<pii>>pq;
    pq.push({0,0});
    dist[0]=0;
    while(!pq.empty()){
        int cur=pq.top().s;
        pq.pop();
        if(vis[cur])continue;
        for(auto i:adj[cur]){
            if(dist[i.f]>dist[cur]+i.s){
                dist[i.f]=dist[cur]+i.s;
                pq.push({dist[i.f],i.f});
            }
        }
    }
    cout<<((dist[1]==1e8)?-1:dist[1]);
}

Compilation message (stderr)

skyscraper.cpp: In function 'int32_t main()':
skyscraper.cpp:56:9: warning: unused variable 'cnt' [-Wunused-variable]
   56 |     int cnt=0;
      |         ^~~
skyscraper.cpp: In function 'void setIO(std::string)':
skyscraper.cpp:31:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |  freopen((name+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
skyscraper.cpp:32:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |  freopen((name+".out").c_str(),"w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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