我刚用一个类创建了一个程序，它允许你简单地用有理数来计算。因此，对于unkerstanding，我的代码是： （不要问为什么它的关系而不是理性我只是愚蠢的命名事物）
main.cpp中：
function rep(b1) {
var s1 = "000000000000";
var s2 = "111111111111";
if (b1 >=1 && b1 <= 12) {
return s2.slice(0, b1) + s1.slice(b1);
} else {
return "no value";
}
}
console.log(rep(6)); // 111111000000
console.log(rep(8)); // 111111110000
Relational.h：
#include <iostream>
#include <stdlib.h>
#include "Relational.h"
using namespace std;
char Relational::lastOperation = 'z';
void main() {
Relational a(4, 5), b(3, 17), c;
c.inverse(a); c.outLast();
c.add(a, b); c.outLast();
c.sub(a, b); c.outLast();
c.mult(a, b); c.outLast();
c.div(a, b); c.outLast();
system("pause");
}
relational.cpp：
class Relational
{
private:
int numerator, denominator;
public:
Relational(int n, int d);
Relational(int n) :numerator(n), denominator(0) {}
Relational() : numerator(0), denominator(0) {}
void setNumerator(int n) { numerator = n; }
void setDenominator(int d) {
if (d<0)
{
numerator = -numerator;
denominator = -d;
}
else denominator = d;
}
int getNumerator() const { return numerator; }
int getDenominator() const { return denominator; }
void out() const { std::cout << "\tNumerator" << numerator << "\n\tDenominator " << denominator << std::endl; }
void outLast();
int inverse(Relational a);
int add(Relational a, Relational b);
int sub(Relational a, Relational b);
int mult(Relational a, Relational b);
int div(Relational a, Relational b);
private:
void shorten();
public:
static int anzahl;
static char lastOperation;
};
所以我遇到的问题是switch语句。 当我运行代码时，它应该如下所示：
#include <iostream>
#include <stdlib.h>
#include "Relational.h"
using namespace std;
Relational::Relational(int n, int d) {
setNumerator(n);
setDenominator(d);
}
int Relational::inverse(Relational a) {
if (a.numerator != 0) {
numerator = a.numerator;
denominator = a.denominator;
lastOperation = 'k';
return 1;
}
else return 0;
}
int Relational::add(Relational a, Relational b) {
numerator = a.numerator*b.denominator + b.numerator*a.denominator;
denominator = a.denominator*b.denominator;
shorten();
lastOperation = 'a';
return 1;
}
int Relational::sub(Relational a, Relational b)
{
numerator = a.numerator*b.denominator - b.numerator*a.denominator;
denominator = a.denominator*b.denominator;
shorten();
lastOperation = 's';
return 1;
}
int Relational::mult(Relational a, Relational b)
{
numerator = a.numerator*b.numerator;
denominator = a.denominator*b.denominator;
shorten();
lastOperation = 'm';
return 1;
}
int Relational::div(Relational a, Relational b)
{
if (b.numerator != 0)
{
numerator = a.numerator*b.denominator;
denominator = a.denominator*b.numerator;
if (denominator<0)
{
numerator = -numerator;
denominator = -denominator;
}
shorten();
lastOperation = 'd';
return 1;
}
else return 0;
}
void Relational::shorten()
{
int x, y, rest;
x = numerator; y = denominator;
if (x<0) x = -x;
while (y>0)
{
rest = x%y;
x = y; y = rest;
}
numerator = numerator / x;
denominator = denominator / x;
}
void Relational::outLast()
{
switch (lastOperation) {
case 'k':
std::cout << "Inverse:" << "\n\tNumerator: " << numerator << "\n\tDenominator: " << denominator << std::endl;
case 'a':
std::cout << "Sum:" << "\n\tNumerator: " << numerator << "\n\tDenominator: " << denominator << std::endl;
case 's':
std::cout << "Difference:" << "\n\tNumerator: " << numerator << "\n\tDenominator: " << denominator << std::endl;
case 'm':
std::cout << "Product:" << "\n\tNumerator: " << numerator << "\n\tDenominator: " << denominator << std::endl;
case 'd':
std::cout << "Quotient:" << "\n\tNumerator: " << numerator << "\n\tDenominator: " << denominator << std::endl;
default:
out();
}
}
相反它看起来像这样：
Inverse:
Nominator: 5
Denominator: 4
Sum:
Nominator: 83
Denominator: 85
Difference:
Nominator: 53
Denominator: 85
Product:
Nominator: 12
Denominator: 85
Quotient:
Nominator: 68
Denominator: 15
我绝对不知道为什么它会给我这个输出 - 我非常感谢你的帮助:)。