Decimal point output format in C ++.

Decimal point output format in C ++.
Exercise 1-5 discounts (discount) in algorithm competition getting started classic)
95 yuan for a piece of clothing. If you spend 300 yuan, you can get off. Enter the number of purchased clothes, and the amount to be paid (unit: yuan). retain two decimal places.
The code I wrote is

#include<iostream>#include<iomanip>using namespace std;int main(void){    double s;    cin>>s;        if(s*95>=300){        cout<<setiosflags(ios::fixed)<<setprecision(2)<<s*95*0.85<<endl;    }         else{        cout<<setiosflags(ios::fixed)<<setprecision(2)<<s*95<<endl;    }            return 0;}

 

So I checked how to display Decimals in different formats in C ++:

Floating point output can be changed with <setiosflags (ios: fixed): never use scientific notation // never use scientific notation. <Setiosflags (ios: scientific): always use scientific notation // use scientific notation. <Resetiosflags (ios: floatfield): restores default (use fixed or scientific notation based on the precision) // reset to the default value. <(Re) setiosflags (ios: showpoint): controls if the trailing zeros and decimal point will be output (default is no) // controls whether zero after the decimal point is displayed. <Setprecision (digits): if fixed or scientific format is selected, controls the number of digits after the decimal place, otherwise controls the total number of significant digits // If fixed or scientific has been determined, the number of digits after the decimal point is controlled; otherwise, all digits are controlled.

#include <iostream>#include <iomanip>using namespace std;int main(void){    double S = 0.000000123;    double A = 456.7;    double B = 8910000000000.0;    cout << "default precision is "         << cout.precision() << endl;    // 6    cout << "    S = " << S << endl;    // 1.23e-07    cout << "    A = " << A << endl;    // 456.7    cout << "    B = " << B << endl;    // 8.91e+12    cout << setiosflags(ios::showpoint)         << "ios::showpoint ON" << endl;    cout << "    S = " << S << endl;    // 1.23000e-07    cout << "    A = " << A << endl;    // 456.700    cout << "    B = " << B << endl;    // 8.91000e+12    cout << resetiosflags(ios::showpoint)         << "ios::showpoint OFF" << endl;    cout << setiosflags(ios::fixed)         << "ios::fixed ON" << endl;    cout << "    S = " << S << endl;    // 0.000000    cout << "    A = " << A << endl;    // 456.700000    cout << "    B = " << B << endl;    // 8910000000000.000000    cout << resetiosflags(ios::fixed)         << setiosflags(ios::scientific)         << "ios::scientific ON" << endl;    cout << "    S = " << S << endl;    // 1.230000e-07    cout << "    A = " << A << endl;    // 4.567000e+02    cout << "    B = " << B << endl;    // 8.910000e+12}

Output:

Default precision is 6
S = 1.23e-007
A = 456.7
B = 8.91e + 012
Ios: showpoint ON
S = 1.23000e-007
A = 456.700
B = 8.91000e + 012
Ios: showpoint OFF
Ios: fixed ON
S = 0.000000
A = 456.700000
B = 8910000000000.000000
Ios: scientific ON
S = 1.23366e-007
A = 4.567000e + 002
B = 8.9425e + 012

--------------------------------
Process exited after 0.02482 seconds with return value 0
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Reference

Https://www.cs.duke.edu/courses/cps149s/fall99/resources/n2.html