Pythagorean Theorem Program Comment, criticize, or whatever

Code:

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#include <iostream>
#include <cmath>
#include <string>

int main()
{
        double SideA, SideB, SideC, Hyp; // Hyp is the Hypotenuse
        std::string GetInfo;

        std::cout << "The Pythagorean Theorem \n\n";
       
        std::cout << "Do you know the hypotenuse? \n>";
        std::cin >> GetInfo;
        std::cout << std::endl;

        std::cin.sync();
       
        if ( GetInfo == "no" ) {

                std::cout << "Enter Your Sides: \n";
                std::cout << "1st: ";
                std::cin >> SideA;
                std::cout << "2nd: ";
                std::cin >> SideB;
                std::cin.ignore();

                Hyp = sqrt( pow( SideA, 2) + pow( SideB, 2));

                std::cout << "Hypotenuse = " << Hyp << std::endl;

        } else if ( GetInfo == "yes" ) {

                std::cout << "Enter Your Data: \n";
                std::cout << "Hypotenuse: ";
                std::cin >> SideC;
                std::cout << "Side: ";
                std::cin >> SideA;
                std::cin.ignore();

                if ( SideC < SideA )
                {
                        std::cerr << "ERROR: The sides can't be bigger then the hypotenuse. \n";

                        return EXIT_FAILURE;
                }

                SideB = sqrt( pow( SideC, 2) - pow( SideA, 2) );

                std::cout << "Missing side = " << SideB << std::endl;

        } else if ( GetInfo != "no" || GetInfo != "yes" ) {

                std::cout << "ERROR: Case Sensitive or Spelling \n";

                return EXIT_FAILURE;
        }

        std::cin.get();

        return(0);
}

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Any advice would be appreciated and I thank you in advance.

Code:

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else if ( GetInfo != "no" || GetInfo != "yes" )

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I don't think this condition matters, but it should be && instead of ||. The way you have it, it will always evaluate to true.

You could get by with SideA, SideB, and Hyp I would think, omitting SideC.
I probably would have organized my 3 sides within a structure.
Also I noticed you have included <string> you can swap all input to all uppercase or all lowercase to omit the caps problems

pow(x, 2) would be more simply expressed as x*x.

Also, one trouble with computing sqrt(x*x + y*y) is that it will overflow for large x and/or y, even if the result (after computing the square root) can be represented in a double.

One common trick to get around this would be;

Code:

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// your approach

Hyp = sqrt( pow( SideA, 2) + pow( SideB, 2));    // blech!!!

// slightly better

Hyp = sqrt(SideA*SideA + SideB*SideB);    //  can overflow for big values of SideA or SideB

// better approach if you want to reduce chances of overflow

double temp;
if (sideA > sideB)
{
  temp = sideB/sideA;                            // guaranteed to produce a result < 1
    Hyp = sideA * sqrt(1.0 + temp*temp); //  1.0 + temp*temp is guaranteed < 2
}
else
{
    temp = sideA/sideB;                            // guaranteed to produce a result <= 1
    Hyp = sideB * sqrt(1.0 + temp*temp); //  1.0 + temp*temp is guaranteed <= 2
}

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Quote:

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Originally Posted by grumpy

Also, one trouble with computing sqrt(x*x + y*y) is that it will overflow for large x and/or y, even if the result (after computing the square root) can be represented in a double.

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The answer to that problem is _hypot. Of course that defeats the purpose of what the OP is trying to learn here though.

Quote:

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Originally Posted by QuestionKing

Also I noticed you have included <string> you can swap all input to all uppercase or all lowercase to omit the caps problems

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Can you show me how to do that ? or send me a example? help would be appreciated.

Thanks.

Here is a tutorial on this site for converting strings to upper case.

Quote:

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Originally Posted by iMalc

The answer to that problem is _hypot. Of course that defeats the purpose of what the OP is trying to learn here though.

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Which is why I didn't bother to mention it .....