Cod sursa(job #545129)

Utilizator PatrunjeluMarginean Bogdan Alexandru Patrunjelu Data 2 martie 2011 19:15:52
Problema Cautare binara Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.67 kb
#include <stdio.h>
#include <vector>
#include <algorithm>
using namespace std;

FILE *fin, *fout;
long n, m, tip, v[100010], numar;

int bsearch0 (int p, int u, int key) 
{
    int m;
    while (p <= u) {
        m = (p + u) / 2;
        if (v[m] <= key)
            p = m + 1;
        else
            u = m - 1;
    }
    m = (p + u) / 2;
    if (v[m] > key) m --;
    if (v[m] == key)
        return m;
    return -1;
}

int bsearch1 (int p, int u, int key) 
{
    int m, n = u;
    while (p < u){
        m = (p + u) / 2;
        if (v[m] <= key)
            p = m + 1;
        else
            u = m;
    }
    m = (p + u) / 2;
    if (v[m] > key)
       -- m;
    return m;
}

int bsearch2 (int p, int u, int key) 
{
    int m;
    while (p < u) {
        m = (p + u) / 2;
        if (v[m] < key)
            p = m + 1;
        else
            u = m;
    }
    m = (p + u) / 2;
    if (v[m] < key)
       ++ m;
    return m;
}

int main()
{
    fin = fopen("cautbin.in", "r");
    fout = fopen("cautbin.out", "w");
    fscanf(fin, "%d", &n);    
    for (int i = 1; i <= n; i++)
    {
        fscanf(fin, "%d", &v[i]);        
    }
    fscanf(fin, "%d", &m);
    for (int i = 0; i < m; i++)
    {
        fscanf(fin, "%d%d", &tip, &numar);
        switch(tip)
        {
            case(0):fprintf(fout, "%d\n", bsearch0(1, n, numar)); break;
            case(1):fprintf(fout, "%d\n", bsearch1(1, n, numar)); break;  
            case(2):fprintf(fout, "%d\n", bsearch2(1, n, numar)); break;
            default: fprintf(fout, "%d\n", -1);    
        }
    }
    fclose(fin);          
    fclose(fout);
    return 0;
}