Info - tema greedy

#include <iostream>
#include <fstream>
using namespace std;
struct spectacol
{
    int X,Y;
} v[101];
int n,i,j,ales,ns;
ifstream fin("spectacole.in");
ofstream fout("spectacole.out");
int main()
{
    fin>>n;
    for(i=1; i<=n; i++)
        fin>>v[i].X>>v[i].Y;
    for(i=1; i<n; i++)
        for(j=i+1; j<=n; j++)
            if(v[i].Y>v[j].Y)
                swap(v[i],v[j]);
    ns=1;
    ales=1;
    for(i=2; i<=n; i++)
        if(v[i].X>=v[ales].Y)
        {
            ns++;
            ales=i;
        }
    fout<<ns;

    return 0;
}