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Commit	Line	Data
	1	/*
	2	* Sample program demonstrating the most important features of the Big
	3	* Integer Library
	4	*/
	5
	6	// Standard libraries
	7	#include <string>
	8	#include <iostream>
	9
	10	// For the BigInteger class itself.
	11	#include "BigInteger.hh"
	12
	13	// For the 4 routines `easy BI/BU <=> string' and `iostream' integration.
	14	#include "BigIntegerUtils.hh"
	15
	16	int main() {
	17	try {
	18	BigInteger a; // a is 0
	19	int b = 535;
	20
	21	a = b; // From int to BigInteger...
	22	b = a; // ...and back, no casts required!
	23	/*
	24	* If a were too big for an int you'd get a runtime exception.
	25	* The Big Integer Library throws C-strings (that is,
	26	* `const char *'s) when something goes wrong. It's a good idea
	27	* to catch them; the `try/catch' construct wrapping all this
	28	* code is an example of how to do this. Some C++ compilers need
	29	* a special command-line option to compile code that uses
	30	* exceptions.
	31	*/
	32
	33	BigInteger c(a); // Copy a BigInteger.
	34
	35	// d is -314159265. The `int' literal is converted to a
	36	// BigInteger.
	37	BigInteger d(-314159265);
	38
	39	// This won't compile because the number is too big to be an
	40	// integer literal.
	41	//BigInteger e(3141592653589793238462643383279);
	42
	43	// Instead you can convert the number from a string.
	44	std::string s("3141592653589793238462643383279");
	45	BigInteger f = easyStringToBI(s);
	46
	47	// You can convert the other way too.
	48	std::string s2 = easyBItoString(f);
	49
	50	// f is stringified and send to std::cout.
	51	std::cout << f << std::endl;
	52
	53	/*
	54	* Let's do some math!
	55	*
	56	* The Big Integer Library provides lots of overloaded operators
	57	* and corresponding assignment operators. So you can do `a + b'
	58	* with BigIntegers just as with normal integers. The named
	59	* methods `add', `divideWithRemainder', etc. are more advanced
	60	* ``put-here operations''; see `BigUnsigned.hh' for details.
	61	*/
	62	BigInteger g(314159), h(265);
	63	// All five ``return-by-value'' arithmetic operators.
	64	std::cout << (g + h) << '\n' << (g - h) << '\n' << (g * h)
	65	<< '\n' << (g / h) << '\n' << (g % h) << std::endl;
	66
	67	BigUnsigned i(0xFF0000FF), j(0x0000FFFF);
	68	// All five ``return-by-value'' bitwise operators.
	69	std::cout.flags(std::ios::hex \| std::ios::showbase);
	70	std::cout << (i & j) << '\n' << (i \| j) << '\n' << (i ^ j) << '\n'
	71	<< (j << 21) << '\n' << (j >> 10) << '\n';
	72	std::cout.flags(std::ios::dec);
	73
	74	// Let's do some heavy lifting and calculate powers of 314.
	75	int maxPower = 10;
	76	BigUnsigned x(1), big314(314);
	77	for (int power = 0; power <= maxPower; power++) {
	78	std::cout << "314^" << power << " = " << x << std::endl;
	79	x *= big314; // A BigInteger assignment operator
	80	}
	81
	82	/*
	83	* If you want to experiment with the library,
	84	* you can add your own test code here.
	85	*/
	86	// std::cout << "Beginning of custom test code:" << std::endl;
	87
	88	} catch(char const* err) {
	89	std::cout << "The library threw an exception:\n"
	90	<< err << std::endl;
	91	}
	92
	93	return 0;
	94	}
	95
	96	/*
	97	Running the sample program produces this output:
	98
	99	3141592653589793238462643383279
	100	314424
	101	313894
	102	83252135
	103	1185
	104	134
	105	0xFF
	106	0xFF00FFFF
	107	0xFF00FF00
	108	0x1FFFE00000
	109	0x3F
	110	314^0 = 1
	111	314^1 = 314
	112	314^2 = 98596
	113	314^3 = 30959144
	114	314^4 = 9721171216
	115	314^5 = 3052447761824
	116	314^6 = 958468597212736
	117	314^7 = 300959139524799104
	118	314^8 = 94501169810786918656
	119	314^9 = 29673367320587092457984
	120	314^10 = 9317437338664347031806976
	121
	122	*/