Cod sursa(job #2280548)

Utilizator cristianabalcanuCristiana Balcanu cristianabalcanu Data 10 noiembrie 2018 20:17:07
Problema Cautare binara Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.7 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin ("cautbin.in");
ofstream fout ("cautbin.out");
int n, m, v[100003], w[100003], c[100003];

int cautarebin(int x)
{
    int st = 1, dr = n, mid;
    while (st<=dr)
    {
        mid = (st+dr)/2;
        if (v[mid] == x)
            return mid;
        else if ( v[mid] < x )
            st = mid + 1;
        else if ( v[mid] > x )
            dr = mid - 1;
    }
    return -1;
}

int cerinta0 ( int x )
{
    int mid = cautarebin(x);
    if ( mid != -1 )
        for (int i = mid + 1 ; i <= n ; i++ )
        {
            if ( v[i] == v[mid])
                mid = i;
            else
                break;
        }
    return mid;
}

int cerinta1 ( int x )
{
    int mid = cautarebin(x);
    if ( mid == -1 )
    {
        for ( int i = n ; i > 0 ; i-- )
        {
            mid = cerinta0(v[i]);
            if ( mid != -1 )
                return mid;
        }
    }
    return mid;
}

int cerinta2( int x )
{
    int mid = cautarebin(x);
    if ( mid != -1 )
        for (int i = mid - 1 ; i > 0 ; i-- )
        {
            if ( v[i] == v[mid])
                mid = i;
            else
                break;
        }
    return mid;
}

int main()
{
    int i;
    fin >> n;
    for ( i = 1 ; i <= n ; i++ )
        fin >> v[i];
    fin >> m;
    for ( i = 1 ; i <= m ; i++ )
        fin >> c[i] >> w[i];
    for ( i = 1 ; i <= m ; i++ )
    {
        if ( c[i] == 0 )
            fout << cerinta0(w[i]) << " ";
        else if ( c[i] == 1 )
            fout << cerinta1(w[i]) << " ";
        else
            fout << cerinta2(w[i]) << " ";

    }
    return 0;
}