#include <iostream>
using namespace std;

void main()
{
    int n;
    cin >> n;

    if( (n >= 1) && (n <= 4) )    cout << "few";
    if( (n >= 5) && (n <=9 ) )    cout << "several";
    if( (n >= 10) && (n <= 19) )    cout << "pack";
    if( (n >= 20) && (n <= 49) )    cout << "lots";
    if( (n >= 50) && (n <= 99) )    cout << "horde";
    if( (n >= 100) && (n <= 249) )    cout << "throng";
    if( (n >= 250) && (n <= 449) )    cout << "swarm";
    if( (n >= 500) && (n <= 999) )    cout << "zounds";
    if( (n >= 1000) )    cout << "legion";

}

Try this test:

461

from 250 to 499 !!!!