Cod sursa(job #2462384)

Utilizator mariusn01Marius Nicoli mariusn01 Data 27 septembrie 2019 11:01:14
Problema Cautare binara Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.63 kb
#include <fstream>

using namespace std;

int v[100010];
int n;
int st, dr, mid, t, i, tip, x;

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

    fin>>n;
    for (i=1;i<=n;i++)
        fin>>v[i];

    fin>>t;
    for (i=1;i<=t;i++) {
        fin>>tip>>x;

        switch (tip) {
        case 0:

            ///

            /// a a a a a x x x x x b b b b b
            /// 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1

            st = 1;
            dr = n;
            while (st<=dr) {
                int mid = (st + dr)/2;
                if (v[mid] <= x)
                    st = mid+1;
                else
                    dr = mid-1;
            }
            if (dr > 0 && v[dr] == x)
                fout<<dr<<"\n";
            else
                fout<<"-1\n";
            break;
        case 1:
            st = 1;
            dr = n;
            while (st<=dr) {
                int mid = (st + dr)/2;
                if (v[mid] <= x)
                    st = mid+1;
                else
                    dr = mid-1;
            }
            fout<<dr<<"\n";
            break;
        case 2:
            /// a a a a a x x x x x b b b b
            /// trebuie primul x si daca nu e x, primul b
            /// 0 0 0 0 0 1 1 1 1 1 1 1 1 1
            st = 1; dr = n;
            while (st <= dr) {
                int mid = (st + dr)/2;
                if (v[mid] < x)
                    st = mid+1;
                else
                    dr = mid-1;
            }
            fout << st <<"\n";
            break;
        }

    }

    return 0;
}