Problema
Money is usually stored as whole cents to avoid rounding errors, and only formatted as dollars when it is shown.
For each item, write the line <name> x<quantity> = <amount>, where amount = quantity × price in cents. After the items, write Total = <amount> with the sum of all lines.
Format every amount as dollars, a dot and exactly two digits of cents, for example 5 → 0.05 and 1250 → 12.50.
Implement format_invoice(names, quantities, cents).
Input
names, quantities, cents: Matching lists describing each item.
Output
Return the item lines followed by the total line.
Restricciones
0 ≤ number of items ≤ 1,000
1 ≤ quantity ≤ 1,000; 0 ≤ cents ≤ 10^6
Ejemplos
Entrada:
cents = [250, 375]
names = ["Tea", "Cake"]
quantities = [2, 1]
Salida esperada:
expected = ["Tea x2 = 5.00", "Cake x1 = 3.75", "Total = 8.75"]Entrada:
std::vector<long long> cents = {250, 375};
std::vector<std::string> names = {"Tea", "Cake"};
std::vector<long long> quantities = {2, 1};
Salida esperada:
std::vector<std::string> expected = {"Tea x2 = 5.00", "Cake x1 = 3.75", "Total = 8.75"};Entrada:
long[] cents = new long[] {250, 375};
string[] names = new string[] {"Tea", "Cake"};
long[] quantities = new long[] {2, 1};
Salida esperada:
string[] expected = new string[] {"Tea x2 = 5.00", "Cake x1 = 3.75", "Total = 8.75"};Explicación
2 × 250 = 500 cents is 5.00 and 375 cents is 3.75; the total is 875 cents: ["Tea x2 = 5.00", "Cake x1 = 3.75", "Total = 8.75"].
Entrada:
cents = [5]
names = ["Gum"]
quantities = [3]
Salida esperada:
expected = ["Gum x3 = 0.15", "Total = 0.15"]Entrada:
std::vector<long long> cents = {5};
std::vector<std::string> names = {"Gum"};
std::vector<long long> quantities = {3};
Salida esperada:
std::vector<std::string> expected = {"Gum x3 = 0.15", "Total = 0.15"};Entrada:
long[] cents = new long[] {5};
string[] names = new string[] {"Gum"};
long[] quantities = new long[] {3};
Salida esperada:
string[] expected = new string[] {"Gum x3 = 0.15", "Total = 0.15"};Explicación
3 × 5 = 15 cents, which is written 0.15: ["Gum x3 = 0.15", "Total = 0.15"].
Cómo abordarlo
Inténtalo primero por tu cuenta y luego abre las pistas una a una.
Pista 1
Do all arithmetic in whole cents.
Pista 2
Split cents into dollars (cents / 100) and the remainder (cents % 100).
Pista 3
Always print the cents with two digits, so 5 cents is 0.05.
Complejidad esperada
O(number of items) time, O(number of items) extra space
Referencias
Este reto está adaptado para CodeUtility. Sigue el enunciado y las restricciones indicadas arriba.