S2 - zad.30 (šuhvelii)

#include <iostream>
#include <vector>

bool f(std:: vector<double> v)
{
    bool jest(false);
    for(int i=0; i<v.size(); i++)
    {
        if((v[i]>v[i+1] && v[i]>v[i-1]) && (v[i+1]<v[i+2])
          || (v[i]<v[i+1] && v[i]<v[i-1]) && (v[i+1]>v[i+2]))
            jest=true;
        else
        {
            jest=false;
            break;
        }
    }
    if(jest) return true;
    else return false;
}

int main()
{
    int n;

    std:: cout << "Unesite broj elemenata niza! ";
    std:: cin >> n;
    std:: vector<double> v(n);
    std:: cout << "Unesite elemente niza: ";
    for(int i=0; i<n; i++)
      std:: cin>> v[i];

    if(f(v))
        std:: cout<< "Oscilatoran je!";
    else std:: cout<< "Nije oscilatoran!";

    return 0;
}