如果差异高于/低于“x”，则比较两个数字，做一些事情

Question

I am wondering whether it is possible to write a code that commpares two numbers and when the second number is 'x' higher/lower than the first number do something. I wrote an example code to make it a bit more clear. Help is appreciated, thanks!

int main() 
{

int first = 0;
int second = 0;

cin >> first;
cin >> second;

if (second = 0.5 > first) //I assumed it would look close to this. This obv isnt working but I cant figure out the correct way.  
{
    cout << "Too big\n";
}
else if (second = 0.5 < first)
{
    cout << "Too low\n";
}
else {
    cout << "Calculation will be made\n";
}

return 0;
}

So in this example, when the second number is between the range of 0.5 compared to the first number the code will proceed.

Answer 1

If you want the amount to check by a certain amount, change your condition to this:

if (second - first > 0.5)
{
    cout << "Too Big!\n";
}
else if (second - first < 0.5)
{
    cout << "Too low\n";
}

This would check if the difference between the 2 nunbers fits the criteria you want. Also, change the types of your numbers to double , since currently truncation will compare the wrong numbers. For example in checking the value with a variable, try this:

int main()
{

    double first = 0;
    double second = 0;
    double x = 0;
    cin >> first;
    cin >> second;
    cin >> x;
    if (second - first > x) {
        cout << "Too Big!\n";
    }
    else if (second - first < x) {
        cout << "Too low\n";
    }
    else {
        cout << "Calculation will be made\n";
    }

    return 0;
}

Answer 2

It is definitely possible. The question is what you want to do. Is

if(second > first + x) {
  cout << "second x or more than x bigger than first" << endl;
} else if(second + x < first) {
  cout << "second x or more smaller than first" << endl;
} else {
  cout << "second - x > first > second + x" << endl;
}

what you like? Of course second, first and x should have the same data type; you shouldn't carelessly mix int and double.

Answer 3

I am not sure about your question but I think you mean:

int main() {
int first;
int second;

cin>>first;
cin>>second;

if (second >first + 0.5) {

} 

If you want second be AT LEAST 0.5 bigger than first. If this is not, reprhase your question please

Answer 4

Use the ternary operator:

int main() 
{

double first;
double second;

cin >> first;
cin >> second;

(second - first > 0.5) ? cout << "Too Big!\n" : ( (second - first < 0.5) ? cout << "Too low\n" : cout << "Calculation will be made\n"; );

}

The format is: < condition > ? < true-case-code > : < false-case-code >;