Cod sursa(job #1426080)

Utilizator patriciaz21Zaharia Patricia patriciaz21 Data 28 aprilie 2015 22:07:14
Problema Cautare binara Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 2.03 kb
#include <fstream>
using namespace std;
ifstream f("cautbin.in");
ofstream g("cautbin.out");
int n, a[100001], x, m, t;
int cautare0(int y)
{
    int st = 1, dr = n, mij;
    while(st <= dr)
    {
        mij = (st + dr)/2;
        if(a[mij] == y && a[mij + 1] != y)
            return mij;
        else if(a[mij == y]) st=mij+1;
        else if(a[mij] > y)
            dr=mij - 1;
        else st = mij + 1;
    }
    return -1;
}
int cautare1(int y)
{
    int st = 1, dr = n, mij;
    while(st <= dr)
    {
        mij = (st + dr)/2;
        if(a[mij] <= y && (a[mij + 1] > y) || mij == n)
            return mij;
        else if(a[mij] == y)
            st = mij + 1;
        else if(a[mij] > y)
            dr = mij-1;
        else st = mij+1;
    }
    return -1;
}
int cautare2(int y)
{
    int st = 1, dr = n, mij;
    while(st <= dr)
    {
        mij = (st + dr)/2;
        if(a[mij] >= y && a[mij-1] < y)
            return mij;
        else if(a[mij] == y)
            dr = mij-1;
        else if(a[mij] > y)
            dr = mij-1;
        else st = mij+1;
    }
    return -1;
}
int main()
{
    f>>n;
    for(int i=1; i<=n; i++)
        f>>a[i];
    f>>m;
    for(int i=1; i<=m; i++)
    {
        f>>t>>x;
        if(t==0)
            g<<cautare0(x)<<'\n';
        else if(t==1)
            g<<cautare1(x)<<'\n';
        else g<<cautare2(x)<<'\n';
    }
    f.close();
    g.close();
    return 0;
}
 
int BS_1(int k)
{
    int li = 0, lf = N;
    while(li <= lf)
    {
        int m = li + ((lf - li) >> 1);
        if(V[m] <= k && ((V[m + 1] > k) || (m + 1 == N)))
            return m + 1;
        if(V[m] > k)
            lf = m - 1;
        else
            li = m + 1;
    }
}
 
int BS_2(int k)
{
    int li = 0, lf = N;
    while(li <= lf)
    {
        int m = li + ((lf - li) >> 1);
        if(V[m] >= k && ((V[m - 1] < k) || (m == 0)))
            return m + 1;
        if(V[m] > k)
            lf = m - 1;
        else
            li = m + 1;
    }
}