我想知道是否有办法设置（＃）所以我的couts是对齐的，如果我改变我的措辞，他们会继续对齐。所以我想我要问的是打印出与指标分开的值，几乎就像有自己的列一样？
示例输出： （原始）
Enter the meal price for the first guest: $45.00
Enter the meal price for the second guest: $50.00
Enter the meal price for the third guest: $100.00
Tax: $13.16
Tip: $41.63
Total Bill: $249.79
Tip Per Person: $13.88
Total Per Person: $83.26
The 3rd guest saved: $16.74
（更改文字）
Enter the meal price for the first guest: $45.00
Enter the meal price for the second guest: $50.00
Enter the meal price for the third guest: $100.00
Tax: $13.16
Gratuity: $41.63
Total Bill: $249.79
Tip Per Person: $13.88
Total Per Person: $83.26
The 3rd guest saved: $16.74
（我的代码）
#include <iomanip> //std:setprecision
#include <iostream>
using namespace std;
int main() {
double ppl1, ppl2, ppl3, meal_total, tax, tip, total, total_bill, per_tip, per_total;
// Get the cost of the meal
cout << "Enter the meal price for the first guest: $";
cin >> ppl1;
// Get the cost of the meal
cout << "Enter the meal price for the second guest: $";
cin >> ppl2;
// Get the cost of the meal
cout << "Enter the meal price for the third guest: $";
cin >> ppl3;
cout << endl;
// Caluates the tax & tip & total
meal_total = ppl1 + ppl2 + ppl3;
tax = meal_total * 6.75 / 100;
tip = (tax + meal_total) * 20 / 100;
total_bill = (tax + meal_total) + tip;
per_tip = tip / 3;
per_total = total_bill / 3;
// I do not have the extra credit in place
cout << "\nTax: $" << setprecision(2) << fixed << tax;
cout << "\nTip: $" << setprecision(2) << fixed << tip;
cout << "\nTotal bill: $" << setprecision(2) << fixed << total_bill;
cout << "\nTip per person: $" << setprecision(2) << fixed << per_tip;
cout << "\nTotal per person: $" << setprecision(2) << fixed << per_total << endl;
// Additional Lab2A adding starts here:
// Adding vars to calulate savings on an per User basis
// then "If" the "Guest total" is greater then 0 we are displaying savings
double ppl1_Tax = ppl1 * 6.75 / 100;
;
double ppl1_Tip = (tax + ppl1) * 20 / 100;
double Price_ppl1 = (ppl1 + ppl1_Tax) + ppl1_Tip;
if ((Price_ppl1 - per_total) > 0) {
cout << "The 1st guest saved: $" << (Price_ppl1 - per_total) << endl;
}
double ppl2_Tax = ppl2 * 6.75 / 100;
;
double ppl2_Tip = (tax + ppl2) * 20 / 100;
double Price_ppl2 = (ppl2 + ppl2_Tax) + ppl2_Tip;
if ((Price_ppl2 - per_total) > 0) {
cout << "The 2nd guest saved: $" << (Price_ppl2 - per_total) << endl;
}
double ppl3_Tax = ppl3 * 6.75 / 100;
;
double ppl3_Tip = (tax + ppl3) * 20 / 100;
double Price_ppl3 = (ppl3 + ppl3_Tax) + ppl3_Tip;
if ((Price_ppl3 - per_total) > 0) {
cout << "The 3rd guest saved: $" << (Price_ppl3 - per_total) << endl;
}
return 0;
}
答案 0 :(得分：2)
您回答了自己的问题，只需使用setw(width)，帮助函数示例：
void print_padded(const std::string& word, int width) {
std::cout << std::left << std::setw(width) << std::setfill(' ') << word;
};
添加更多信息，如果您不知道words是否会大于width，请跟踪最大的word并设置width } word.length() + 2或类似的东西。
答案 1 :(得分：0)
你可以从昨天的答案中获取灵感：
How to write in text file by line and column using C++
同样，您可以在实际打印之前收集可打印的行。然后，您可以在打印前推断出标题列的最小所需宽度。
同时，删除代码中的重复并使用富有表现力的名称也可以改善它：
#include <iomanip> //std:std::setprecision
#include <iostream>
#include <vector>
#include <algorithm>
struct Pricing {
double _base;
static constexpr double tax_rate = 0.0675;
static constexpr double tip_rate = 0.20;
double tax() const { return _base * tax_rate; }
double tip() const { return with_tax() * tip_rate; }
double with_tax() const { return _base * (1 + tax_rate); }
double with_tip() const { return with_tax() * (1 + tip_rate); }
};
struct DinnerParty {
struct Party {
std::string name;
double base_price;
};
using Parties = std::vector<Party>;
DinnerParty(Parties parties) : _parties(std::move(parties)) { }
Parties const& parties() const { return _parties; }
size_t head_count() const { return _parties.size(); }
Pricing total() const { return { base_total() }; }
Pricing per_head() const { return { base_total()/head_count() }; }
private:
Parties const _parties;
double base_total() const {
double base = 0;
for (auto& p : _parties) base += p.base_price;
return base;
}
};
template <typename ColDefs>
void printTable(ColDefs const& cols) {
if (cols.empty())
return;
// find widest caption
std::vector<int> widths;
for (auto& col : cols)
widths.push_back(col.caption.length());
int width = 2 + *std::max_element(widths.begin(), widths.end());
for (auto& col : cols)
{
if (col.caption.empty())
std::cout << "\n";
else std::cout
<< std::left << std::setw(width) << (col.caption+": ") << "$"
<< std::right << std::setprecision(2) << std::fixed << col.value << "\n";
}
}
int main() {
std::cin.exceptions(std::ios::failbit);
auto promptPrice = [](auto name) {
std::cout << "Enter the meal price for " << name << ": $";
double base_price;
std::cin >> base_price;
return DinnerParty::Party { name, base_price };
};
DinnerParty dinner({
promptPrice("first guest"),
promptPrice("second guest"),
promptPrice("third guest"),
});
struct Row { std::string caption; double value; };
Pricing total = dinner.total(),
per_head = dinner.per_head();
std::vector<Row> rows {
{"Tax", total.tax() },
{"Tip", total.tip() },
{"Total bill", total.with_tip() },
{"Tip per person", per_head.tip() },
{"Total per person", per_head.with_tip() },
{"", 0}, // empty row
};
// Additional Lab2A adding starts here:
// Adding vars to calulate savings on an per User basis
// then "If" the "Guest total" is greater then 0 we are displaying savings
for (auto& party : dinner.parties()) {
Pricing personal {party.base_price};
double net_gain = personal.with_tip() - per_head.with_tip();
if (net_gain > 0)
rows.push_back({party.name + " saved", net_gain });
}
printTable(rows);
}
打印
Enter the meal price for first guest: $ 17
Enter the meal price for second guest: $ 32
Enter the meal price for third guest: $ 25
Tax: $5.00
Tip: $15.80
Total bill: $94.79
Tip per person: $5.27
Total per person: $31.60
second guest saved: $9.39
third guest saved: $0.43