基本数据类型的运算

谁践踏了优雅 2022-08-25 08:49 171阅读 0赞

#include <iostream >
    #include <cstdio>
    using namespace std;
    void test_int()
    {
    	printf("\ntest int:\n");
    	int a = 100000;
    	cout << "100000 * 100000 = " << a * a << endl;
    	cout << " 14  / 5  = " << 14 / 5 << endl;
    	cout << " 14  % 5  = " << 14 % 5 << endl;
    	cout << " -14 / 5  = " << -14 / 5 << endl;
    	cout << " -14 % 5  = " << -14 % 5 << endl;
    	cout << " 14  / -5 = " << 14 / -5 << endl;
    	cout << " 14  % -5 = " << 14 % -5 << endl;
    	cout << " -14 / -5 = " << -14 / -5 << endl;
    	cout << " -14 % -5 = " << -14 % -5 << endl;
    }
    void test_double()
    {
    	printf("\ntest double:\n");
    	double c, d, z;
    	c = 1.0; d = 0.0;
    	cout << " 1.0  / 0.0 = " << c/d << endl;
    	c = -1.0; d = 0.0;
    	cout << " -1.0 / 0.0 = " << c/d << endl;
    	c = 0.0; d = 0.0;
    	cout << " 0.0  / 0.0 = " << c/d << endl;
    	z = 1.0;
    	cout << " z = 1.0; z = " << z << endl;
    	z /= 12345678912345.0;
    	
    	cout << " z /= 12345678912345.0; z = " << z << endl;
    	z += 1.0;
    	cout << " z += 1.0; z = " << z << endl;
    	z -= 1.0;
    	cout << " z -= 1.0; z = " << z << endl;
    	z *= 12345678912345.0;
    	cout << " z *= 12345678912345.0; z == " << z << endl;
    }
    void test_bool()
    {
    	printf("\ntest bool:\n");
    	cout << "(1 <= 2) = " << (1 <= 2) << endl;
    	cout << "(3 == 4) = " << (3 == 4) << endl;
    	cout << "(5 != 6 && -7 <= 10) = " << (5 != 6 && -7 <= 10) << endl;
    	cout << "(1234 & 5678) = " << (1234 & 5678) << endl;
    	cout << "(1 << 16) = " << (1 << 16) << endl;
    }
    void test_order()
    {
    	printf("\ntest order:\n");
    	int a = 2, b = 3;
    	cout << "(a++) * (a+2*b) * (b++) = " << (a++) * (a+2*b) * (b++) << endl;
    }
    void test_char()
    {
    	printf("\ntest char:\n");
    	cout << "'A ' + 2 = " << 'A' + 2 << endl;
    	cout << "(char)('A ' + 2) = " << (char)('A' + 2) << endl;
    	cout << "'z' - 'f' = " << 'z' - 'f' << endl;
    }
    int main()
    {
    	test_int();
    	test_double();
    	test_bool();
    	test_char();
    	test_order();
    	
    	return 0;
    }
    
    /*
    
    test int:
    100000 * 100000 = 1410065408
     14  / 5  = 2
     14  % 5  = 4
     -14 / 5  = -2
     -14 % 5  = -4
     14  / -5 = -2
     14  % -5 = 4
     -14 / -5 = 2
     -14 % -5 = -4
    
    test double:
     1.0  / 0.0 = inf
     -1.0 / 0.0 = -inf
     0.0  / 0.0 = nan
     z = 1.0; z = 1
     z /= 12345678912345.0; z = 8.1e-014
     z += 1.0; z = 1
     z -= 1.0; z = 8.10463e-014
     z *= 12345678912345.0; z == 1.00057
    
    test bool:
    (1 <= 2) = 1
    (3 == 4) = 0
    (5 != 6 && -7 <= 10) = 1
    (1234 & 5678) = 1026
    (1 << 16) = 65536
    
    test char:
    'A ' + 2 = 67
    (char)('A ' + 2) = C
    'z' - 'f' = 20
    
    test order:
    (a++) * (a+2*b) * (b++) = 48
    
    */