gornja trougaona matrica

#include <iostream>
#include<vector>

typedef std::vector<std::vector<int>> Matrica;

bool funkcija(Matrica m)
{
    bool trougaona=false;
    for (int i(0); i<m.size(); i++)
    {
        for (int j(0); j<m[0].size(); j++)
        {
          if(i>0 && j<i)
            {
                if(m[i][j] == 0)
                trougaona = true;
          }
        }
    }
    return trougaona;
}
int main()
{
    int m, n;
    std::cout<<"Unesi dimenziju matrice:\n";
    std::cin>>m>>n;
    Matrica mat(m, std::vector<int>(n));
    std::cout<<"Unesi clanove matrice:\n";
    for (int i(0); i<m; i++)
    {
        for(int j(0); j<n; j++)
        {
            std::cin>>mat[i][j];
        }
    }
    bool rez = funkcija(mat);
    std::cout<<"\n rezultat: "<< rez;




    return 0;
}