Cod sursa(job #2029135)

Utilizator HumikoPostu Alexandru Humiko Data 29 septembrie 2017 15:25:37
Problema Cautare binara Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.09 kb
#include <fstream>
using namespace std;

ifstream fin ("cautbin.in");
ofstream fout ("cautbin.out");

int v[100001];

int cautbin (int key, int logaritm, int n)
{
    int best = 0;
    for ( int i = logaritm; i >= 0; --i )
        if ( best + (1<<i) <= n && v[best+(1<<i)] <= key )
            best += (1<<i);
    return best;
}

int main()
{
    int n, m, logaritm = 0, p = 1;
    fin>>n;
    for ( int i = 1; i <= n; ++i )
        fin>>v[i];
    while ( p <= n )
    {
        p *= 2;
        logaritm++;
    }
    fin>>m;
    while ( m-- )
    {
        int tip, key;
        fin>>tip>>key;
        if ( tip == 0 )
        {
            int pos = cautbin (key, logaritm, n);
            if ( v[pos] == key )
                fout<<pos<<'\n';
            else
                fout<<'-1'<<'\n';
        }
        else
        {
            if ( tip == 1 )
            {
                fout<<cautbin(key, logaritm, n)<<'\n';
            }
            else
            {
                fout<<cautbin(key-1, logaritm, n)+1<<'\n';
            }
        }
    }
}