Series

#include <iostream>
#include <string>

using namespace std;

int main() {
    double budget, cash;
    cin >> budget;

    int volume;
    cin >> volume;

    string name;

    for (int i = 0; i < volume; i++) {
        cin.ignore();
        getline(cin, name);
        cin >> cash;

        if (name == "Thrones") {
            cash /= 2;
        }
        else if (name == "Lucifer") {
            cash *= 0.6;
        }
        else if (name == "Protector") {
            cash *= 0.7;
        }
        else  if (name == "TotalDrama") {
            cash *= 0.8;
        }
        else  if (name == "Area") {
            cash *= 0.9;
        }

        budget -= cash;
    }

    if (budget >= 0) {
        printf("You bought all the series and left with %.2f lv.\n", budget);
    }
    else {
        printf("You need %.2f lv. more to buy the series!\n", abs(budget));
    }

    return 0;
}

Решение с тернарен оператор:

#include <iostream>
#include <string>

using namespace std;

int main() {
    double budget, cash;
    cin >> budget;

    int volume;
    cin >> volume;

    string name;

    for (int i = 0; i < volume; i++) {
        cin.ignore();
        getline(cin, name);
        cin >> cash;

        cash *=
            name == "Thrones" ? 0.5 :
            name == "Lucifer" ? 0.6 :
            name == "Protector" ? 0.7 :
            name == "TotalDrama" ? 0.8 :
            name == "Area" ? 0.9 : 1;

        budget -= cash;
    }

    budget >= 0 ?
        printf("You bought all the series and left with %.2f lv.\n", budget) :
        printf("You need %.2f lv. more to buy the series!\n", abs(budget));

    return 0;
}