formatdemo.cpp

来自「C++&datastructure书籍源码,以前外教提供现在与大家共享」· C++ 代码 · 共 42 行

#include <iostream>
#include <iomanip>
#include <cmath>
using namespace std;

// formatting using manipulators


int main()
{
	const double CENTIPI = 100 * acos(-1); // arccos(-1) = PI
	const int MAX = 10;
	const int TAB = 15;
	int k;

    cout << "default setting " << CENTIPI << ", with setprecision(4), "
		 << setprecision(4) << CENTIPI << endl;

	cout << "\nfixed floating-point, precision varies, fixed/scientific\n" << endl;
	for(k=0; k < MAX; k++)
	{  cout << left << "pre. " << k << "\t" << setprecision(k) << setw(TAB)
	        << fixed << CENTIPI <<  scientific  << "\t" << CENTIPI << endl; 
	}

	cout << endl << "width and justification vary, fixed, precision 2\n" << endl;
	cout << setprecision(2) << fixed;
	for(k=3; k < MAX+3; k++)
	{  cout << "wid. " << k << "\t+" << left << setw(k) << CENTIPI << right 
	        << "+\t\t-" << setw(k) << CENTIPI << "-" << endl;
	}

	cout << endl << "repeated, fill char = @\n" << endl;
	cout << setfill('@');
	for(k=3; k < MAX+3; k++)
	{  cout << "wid. " << k << "\t+" << left << setw(k) << CENTIPI << right 
	        << "+\t\t-" << setw(k) << CENTIPI << "-" << endl;
	}


    return 0;
}