Răspuns :
Am atasat 2 imagini cu explacitiile si 2 notepaduri cu codurile.
Rezolvare 1 - folosind formula matematica:
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
long long n, delta, rasp;
cin >> n;
delta = 1 + 8 * (n - 1);
rasp = (1 + sqrt(delta)) / 2;
cout << rasp;
return 0;
}
Rezolvare 2 - folosind dinamica:
#include <iostream>
using namespace std;
int main()
{
long long n, c = 1;
cin >> n;
while (n - c > 0) n -= c, ++c;
cout << c;
return 0;
}
![Vezi imaginea Аноним](https://ro-static.z-dn.net/files/d25/d3d2a50b4c54755b8366b36404bb917c.png)
![Vezi imaginea Аноним](https://ro-static.z-dn.net/files/db0/808bcc9fc4ac40c21511b23d90bc1481.png)