Job sequence with deadline greedy algorithm easy

#include<bits/stdc++.h>
using namespace std;
int n,d[100],p[100],j[1000],s[1000];
class JobSequence{
public:
    void input()
    {
        cin>>n;
        for(int i=1;i<=n;i++)
        {
            cin>>p[i]>>d[i];
            s[i]=i;
        }
    }
    int find_sequence()
    {
        selection_sort();
        d[0] = j[0] = 0;
        j[1] = 1;
        int k = 1;
        for(int i =2; i<=n; i++)
        {
            int r = k;
            while(d[i] < d[j[r]] && d[j[r]] != r)
            {
                r = r-1;
            }
            if(d[i] >= d[j[r]] && d[i] > r)
            {
                for(int q=k; q>=r+1; q--)
                    j[q+1] = j[q];
                j[r+1] = i;
                k = k+1;
            }
        }
        return k;
    }
    void selection_sort()
    {
        for(int i =1;i<=n;i++)
        {
            int max_index = i;
            for(int j =i+1;j<=n;j++)
            {
                if(p[j]>p[max_index])
                    max_index = j;
            }
            swap(p[i],p[max_index]);
            swap(d[i],d[max_index]);
            swap(s[i],s[max_index]);
        }
    }
};
int main()
{
    freopen("input.txt","r",stdin);
    JobSequence js;
    js.input();
    int total_job=js.find_sequence();
    for(int i =1;i<=n;i++)
        cout<<p[i]<<" "<<d[i]<<" "<<s[i]<<endl;

    cout<<"Total selected job = "<<total_job<<endl;

    cout<<endl<<"Sequence of selected job =  ";
    for(int i =1;i<=total_job;i++)
    {
         cout<<j[i]<<" ";
    }
}
/*
input
5

15 3
10 1
5 2
1 2
20 2
*/