Найти сумму ряда S = 15 + 16 + 17 + ... + n.

С++#include<iostream>using namespace std;main(){ int a, s; cin >> a; for(int i = 15; i <= a; i++) s += i; cout << s;}Pythona = int(input())s = 0for i in range(15, a + 1):    s += iprint(s)Pascalvar a, s, i: integer;beginread(a);for i := 15 to a do s += i;write(s);end.