Submission #103978

#	Time	Username	Problem	Language	Result	Execution time	Memory
103978		LittleFlowers__	Jakarta Skyscrapers (APIO15_skyscraper)	C++14	0 / 100	4 ms	1024 KiB

skyscraper

#include <bits/stdc++.h>
using namespace std;
#define in ({int x=0;int c=getchar(),n=0;for(;!isdigit(c);c=getchar()) n=(c=='-');for(;isdigit(c);c=getchar()) x=x*10+c-'0';n?-x:x;})
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rnd(int l,int r){return l+rng()%(r-l+1);}
#define fasty ios_base::sync_with_stdio(false),cin.tie(nullptr);
#define task "SKYSCRAPER"
#define forinc(a,b,c) for(int a=b,_c=c;a<=_c;++a)
#define fordec(a,b,c) for(int a=b,_c=c;a>=_c;--a)
#define forv(a,b) for(auto&a:b)
#define fi first
#define se second
#define pb push_back
#define ii pair<int,int>
#define mt make_tuple
#define all(a) a.begin(),a.end()
#define reset(f, x) memset(f, x, sizeof(f))
#define bit(x,i) ((x>>(i-1))&1)
#define on(x,i) (x|(1ll<<(i-1)))
#define off(x,i) (x&~(1<<(i-1)))

const int N=30010;

int n,m;
int b[N],p[N];
queue<ii> q;
vector<int> val[N];
map<int,map<int,int>> f;

void add(int x,int y,int i)
{
    if(x<1 || x>n) return;
    if(f[x][i]>f[y][i]+1 || !f[x][i]){
        f[x][i]=f[y][i]+1, q.push({x,i});
    }
}

main()
{
    //freopen(task".inp","r",stdin);
    //freopen(task".out","w",stdout);
    n=in,m=in;
    forinc(i,1,m) b[i]=in+1,p[i]=in,val[b[i]].pb(p[i]);
    q.push({b[1],p[1]}); f[b[1]][p[1]]=1;
    while(q.size())
    {
        ii u=q.front(); q.pop(); int x=f[u.fi][u.se];
        if(u.fi==2) return cout<<f[u.fi][u.se]-1,0;
        forv(i,val[u.fi]) if(f[u.fi][i]>x || !f[u.fi][i])
            f[u.fi][i]=x, q.push({u.fi,i});
        add(u.fi-u.se,u.fi,u.se);
        add(u.fi+u.se,u.fi,u.se);
    }
    cout<<-1;
}

Compilation message (stderr)

skyscraper.cpp:38:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main()
      ^

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