#include <iostream>

// THIS IS MORE CHALLENGING
//
// Canada uses a progressive income-tax system. This means
// that a higher tax rate applies only to the portion of
// taxable income that falls within a higher tax bracket.
//
// For this exercise, we will use the 2021 Canadian federal
// income-tax brackets:
//
//     Taxable income                       Tax rate
//
//     First $49,020                           15%
//     From $49,020 to $98,040                 20.5%
//     From $98,040 to $151,978                26%
//     From $151,978 to $216,511               29%
//     Above $216,511                           33%
//
// These are the 2021 federal tax brackets. Actual income-tax
// calculations also involve credits, deductions, provincial
// or territorial taxes and other considerations. This
// exercise considers only the federal bracket calculation.
//
// The important point is that reaching a higher tax bracket
// does NOT cause all of your income to be taxed at the
// higher rate.
//
// For example, someone with $50,000 of taxable income pays
//
//     15%   on the first $49,020,
//     20.5% on the remaining $980.
//
// Someone with $100,000 of taxable income pays
//
//     15%   on the first $49,020,
//     20.5% on the next  $49,020,
//     26%   on the remaining $1,960.
//
// Someone with $200,000 of taxable income pays
//
//     15%   on the first $49,020,
//     20.5% on the next  $49,020,
//     26%   on the next  $53,938,
//     29%   on the remaining $48,022.
//
// The widths of the first four tax brackets are therefore:
//
//           $0 to  $49,020:    $49,020
//      $49,020 to  $98,040:    $49,020
//      $98,040 to $151,978:    $53,938
//     $151,978 to $216,511:    $64,533
//
// Everything above $216,511 is taxed at 33%.
//
// Because we are using integer arithmetic, calculate
// percentages as follows:
//
//     15%   of amount:    (amount*15)/100
//     20.5% of amount:    (amount*205)/1000
//     26%   of amount:    (amount*26)/100
//     29%   of amount:    (amount*29)/100
//     33%   of amount:    (amount*33)/100
//
// Integer division means that any fractional dollar of tax
// calculated for a bracket will be discarded in this
// simplified exercise.
//
// Write a program that asks the user for a non-negative
// integer taxable income and calculates the federal income
// tax according to these brackets.
//
// If the user enters a negative income, immediately
// terminate the program by returning 0 from main().

// Function declarations
int main();

// Function definitions
int main() {
    int income{};

    std::cout << "Enter your taxable income: ";
    std::cin >> income;

    if ( income < 0 ) {
        return 0;
    }

    // Calculate the federal income tax here.

    int income_tax{};

    std::cout << "You owe $" << income_tax
              << " in federal income tax."
              << std::endl;

    return 0;
}









































// Hint:
//
// One approach is to keep track of the amount of income
// that has not yet been taxed.
//
// Begin with the first bracket.
//
// If all the remaining income fits within that bracket,
// tax all of it at that rate.
//
// Otherwise:
//
//     1. tax the entire bracket,
//     2. subtract the width of that bracket from the
//        remaining income, and
//     3. continue with the next bracket.
//
// For example, suppose the remaining income is $100,000.
//
// After taxing the first $49,020, the amount remaining is
//
//     100000 - 49020 = 50980.
//
// After taxing the next $49,020, the amount remaining is
//
//     50980 - 49020 = 1960.
//
// That final $1,960 is then taxed at 26%.









































// Here is one solution:

/*
int main() {
    int income{};

    std::cout << "Enter your taxable income: ";
    std::cin >> income;

    if ( income < 0 ) {
        return 0;
    }

    int income_tax{};

    // Tax the first $49,020 at 15%.

    if ( income <= 49020 ) {
        income_tax += (income*15)/100;
    } else {
        income_tax += (49020*15)/100;
        income -= 49020;

        // Tax the next $49,020 at 20.5%.

        if ( income <= 49020 ) {
            income_tax += (income*205)/1000;
        } else {
            income_tax += (49020*205)/1000;
            income -= 49020;

            // Tax the next $53,938 at 26%.

            if ( income <= 53938 ) {
                income_tax += (income*26)/100;
            } else {
                income_tax += (53938*26)/100;
                income -= 53938;

                // Tax the next $64,533 at 29%.

                if ( income <= 64533 ) {
                    income_tax += (income*29)/100;
                } else {
                    income_tax += (64533*29)/100;
                    income -= 64533;

                    // Tax all remaining income at 33%.

                    income_tax += (income*33)/100;
                }
            }
        }
    }

    std::cout << "You owe $" << income_tax
              << " in federal income tax."
              << std::endl;

    return 0;
}
*/







































// An alternative approach:
//
// Instead of nesting the conditional statements, we can
// process one tax bracket at a time.
//
// After processing each bracket, subtract its width from
// 'income'. If there is still income remaining, process
// the next bracket.
//
// This produces code with less nesting:

/*
int main() {
    int income{};

    std::cout << "Enter your taxable income: ";
    std::cin >> income;

    if ( income < 0 ) {
        return 0;
    }

    int income_tax{};

    // Tax up to the first $49,020 at 15%.

    if ( income <= 49020 ) {
        income_tax += (income*15)/100;
    } else {
        income_tax += (49020*15)/100;
    }

    income -= 49020;

    // If income remains, tax up to the next $49,020
    // at 20.5%.

    if ( income > 0 ) {
        if ( income <= 49020 ) {
            income_tax += (income*205)/1000;
        } else {
            income_tax += (49020*205)/1000;
        }

        income -= 49020;
    }

    // If income remains, tax up to the next $53,938
    // at 26%.

    if ( income > 0 ) {
        if ( income <= 53938 ) {
            income_tax += (income*26)/100;
        } else {
            income_tax += (53938*26)/100;
        }

        income -= 53938;
    }

    // If income remains, tax up to the next $64,533
    // at 29%.

    if ( income > 0 ) {
        if ( income <= 64533 ) {
            income_tax += (income*29)/100;
        } else {
            income_tax += (64533*29)/100;
        }

        income -= 64533;
    }

    // Any remaining income is taxed at 33%.

    if ( income > 0 ) {
        income_tax += (income*33)/100;
    }

    std::cout << "You owe $" << income_tax
              << " in federal income tax."
              << std::endl;

    return 0;
}
*/