Cod sursa(job #957899)

Utilizator manutrutaEmanuel Truta manutruta Data 6 iunie 2013 13:12:36
Problema Cautare binara Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.73 kb
#include <iostream>
#include <fstream>
using namespace std;

ifstream f("cautbin.in");
ofstream g("cautbin.out");

int n, a[100000];

int cautbin0 (int st, int dr, int key) {
    int middle;

    while (st <= dr) {
        middle = (st + dr) / 2;
        if (a[middle] <= key)
            st = middle + 1;
        else
            dr = middle - 1;
    }
    middle = (st + dr) / 2;

    if (a[middle] > key) middle --;
    if (a[middle] == key)
        return middle;
    return -1;
}

int cautbin1 (int st, int dr, int key) {
    int middle, n = dr;

    while (st < dr){
        middle = (st + dr) / 2;
        if (a[middle] <= key)
            st = middle + 1;
        else
            dr = middle;
    }

    middle = (st + dr) / 2;
    if (a[middle] > key)
       -- middle;
    return middle;
}

int cautbin2 (int st, int dr, int key) {
    int middle;

    while (st < dr) {
        middle = (st + dr) / 2;
        if (a[middle] < key)
            st = middle + 1;
        else
            dr = middle;
    }

    middle = (st + dr) / 2;
    if (a[middle] < key)
       ++ middle;
    return middle;
}

int m;
int main()
{
    f >> n;
    for(int i = 1; i <= n; i++)
        f >> a[i];

    f >> m;
    for(int i = 1; i <= m; i++)
    {
        int key;
        f >> key;
        int x;
        f >> x;

        switch(key)
        {
            case 0:
                g << cautbin0(1, n, x) << endl;
                break;
            case 1:
                g << cautbin1(1, n, x) << endl;
                break;
            case 2:
                g << cautbin2(1, n, x) << endl;
                break;
        }
    }


    f.close();
    g.close();
    return 0;
}