753A - Santa Claus and Candies

#include <iostream>
#include <set>
#include <cmath>
using namespace std;

int main() {
    int n,aux,i=1,cont=0,sum=0;
    set<int> s;
    cin>>n;
    while(sum<n){
        cont++;
        s.insert(cont);
        sum=sum+cont;
    }
    if (sum>n) {cont--;s.erase(1);i=2;sum--;}
    while(sum!=n){
        s.erase(i);
        s.insert(i-1);
        i++;
        sum--;
    }
    set<int>::iterator it;
    cout<<cont<<endl;
    i=0;
    for (it=s.begin(); it!=s.end(); it++){
        i++;
        if (i==cont)
            cout <<*it<<endl;
        else
            cout <<*it<<' ';
    }
    return 0;
}