我需要循环并在给出字符串 -1 时终止程序

Question

#include <iostream>
#include <cmath>
using namespace std;
int main (){
//Written By: Hannah Stang
//Reads a Binary number and converts it to a decimal
long decimal = 0, remainder, number, base = 1;
long bin;
    cout << "Enter a binary number: ";
    cin >> number;
    bin = number;
    while (number > 0)
    {
        remainder = number % 10;
        decimal = decimal + remainder * base;
        base = base * 2;
        number = number / 10;
    }
cout << "Conversion to decimal: " << decimal << endl;
return 0;
}

我遇到的主要问题是试图让程序运行不止一次。我需要它不断重复，直到我输入 -1 作为值。

Answer 1

您可以执行以下操作：

#include <iostream>
#include <cmath>
using namespace std;
int main (){
//Written By: Hannah Stang
//Reads a Binary number and converts it to a decimal
  long decimal = 0, remainder, number, base = 1;
  long bin;
  cout << "Enter a binary number: ";
  cin >> number;
  while (number != -1)
  {
    bin = number;
    while (number > 0)
    {
        remainder = number % 10;
        decimal = decimal + remainder * base;
        base = base * 2;
        number = number / 10;
    }
    cout << "Conversion to decimal: " << decimal << endl;
    cout<< "Enter a binary number: ";
    cin>> number;
  }
  return 0;
}

换句话说，只需将主代码嵌入到条件为数字不等于-1的循环中

请注意，我正在读取循环体末尾的数字，因此如果用户输入 -1，他会立即退出。

Answer 2

尝试移动 while 循环并从 number 初始化为 1 开始：

long decimal = 0, remainder, number=1, base = 1;

while (number > 0)
{
    cout << "Enter a binary number: ";
    cin >> number;
    bin = number;
    remainder = number % 10;
    decimal = decimal + remainder * base;
    base = base * 2;
    number = number / 10;
    cout << "Conversion to decimal: " << decimal << endl;
}

或者你可以这样做：

while (1)
{
    cout << "Enter a binary number: ";
    cin >> number;
    if(number == -1)
    {
        cout<<"Program exiting.";
        break;
    }
    bin = number;
    remainder = number % 10;
    decimal = decimal + remainder * base;
    base = base * 2;
    number = number / 10;
   cout << "Conversion to decimal: " << decimal << endl;
}