Question

我试着制作一个非常简单的计算器。到目前为止，这就是我所拥有的，但我得到了非常模糊的答案。比如，对于乘以2和2我得到1550532996.所有帮助赞赏。

#include <iostream>
using namespace std;

int main()
{
int x;
int b;
int k;
int sum=x+b;
int difference=x-b;
int product=x*b;
int quotient=x/b;
cout<<"Enter a number"<<endl;
cin>>x;
cout<<"Enter another number."<<endl;
cin>>b;
cout<<"What do you want to do with these numbers? Enter 1 for addition, 2 for subtraction, 3 for multiplication, and 4 for division"<<endl;
cin>>k;
    switch (k){

    case 1:
    cout<<sum<<endl;
    break;

    case 2:
    cout<<difference<<endl;
    break;

    case 3:
    cout<<product<<endl;
    break;

    case 4:
    cout<<quotient<<endl;
    break;
    }

}

Answer 1

替换

int x;
int b;
int k;
int sum=x+b;
int difference=x-b;
int product=x*b;
int quotient=x/b;
cout<<"Enter a number"<<endl;
cin>>x;
cout<<"Enter another number."<<endl;
cin>>b;
cout<<"What do you want to do with these numbers? Enter 1 for addition, 2 for subtraction, 3 for multiplication, and 4 for division"<<endl;
cin>>k;

通过

int x;
int b;
int k;
cout<<"Enter a number"<<endl;
cin>>x;
cout<<"Enter another number."<<endl;
cin>>b;
cout<<"What do you want to do with these numbers? Enter 1 for addition, 2 for subtraction, 3 for multiplication, and 4 for division"<<endl;
cin>>k;
int sum=x+b;
int difference=x-b;
int product=x*b;
int quotient=x/b;

int sum = x + b不是函数，只是设置为（x + b）的变量。

Answer 2

问题在于您在读取用户输入之前进行了计算。由于你的变量是未初始化的，它们会保留一些随机的东西（可能是之前在内存中的那个位置）。这就是你得到错误结果的原因。

int x;
int b;
int k;
int sum=x+b;
int difference=x-b;
int product=x*b;
int quotient=x/b;
cout<<"Enter a number"<<endl;
cin>>x;
cout<<"Enter another number."<<endl;
cin>>b;
cout<<"What do you want to do with these numbers? Enter 1 for addition, 2 for subtraction, 3 for multiplication, and 4 for division"<<endl;
cin>>k;

应该改为：

int x;
int b;
int k;
cout<<"Enter a number"<<endl;
cin>>x;
cout<<"Enter another number."<<endl;
cin>>b;
int sum=x+b;
int difference=x-b;
int product=x*b;
int quotient=x/b;
cout<<"What do you want to do with these numbers? Enter 1 for addition, 2 for subtraction, 3 for multiplication, and 4 for division"<<endl;
cin>>k;

简单计算器

2 个答案: