wrong output...

the purpose of the program is to add||subtract||multiply||divide fractions, everything works fine, but when it comes to the output.
The difference between the result of the operation and 1.00 (
diff=(1.00-result) is not displayed in fraction format that i intended

heres the code,

Code:

---

____________________________________________________

//----------------------------------------------------------------
cout<<"\n\n\a______________________________________________\n\n";
cout<<"\t\t"<<frac.oneFRAC<<"/"<<frac.twoFRAC<<" "<<oper<<" "<<frac.numTWO<<"/"<<frac.denomTWO<<" = ";
                                               
                if (result==three_quarter)
                cout<<"3/4"<<endl;
                else
                if (result==one_half)
                cout<<" 1/2"<<endl;
                else
                if (result==one_quarter)
                cout<<"1/4"<<endl;
                else
                if (result==seven_eights)
                        cout<<"7/8"<<endl;
                else
                if (result==five_eights)
                        cout<<"5/8"<<endl;
                else
                if (result==three_eights)
                        cout<<"3/8"<<endl;
                else
                if (result==one_eight)
                        cout<<"1/8"<<endl;
                else
                if (result==one_sixteen)
                        cout<<"1/16"<<endl;
                else
                if (result==one_third)
                        cout<<"1/3"<<endl;
                else
                if (result==two_third)
                        cout<<"2/3"<<endl;
                else
                if(result==two_fifths)
                cout<<"2/5"<<endl;
                else
                if(result==one_tenths)
                cout<<"1/10"<<endl;
                else
                if(result==nine_tenths)
                cout<<"9/10"<<endl;
                else
                        cout<<setprecision(3)<<setiosflags(ios::fixed|ios::showpoint)<<result<<endl<<endl;

//----------------------------------------
                cout<<"            The difference from a whole (1.0) is:\n"<<endl;
                cout<<"                1.0 - "<<result<<" = ";
                {
                diff=1-result;
               
                if (diff==three_quarter)
                cout<<"3/4"<<endl;
                if (diff==one_half)
                cout<<" 1/2"<<endl;
                if (diff==one_quarter)
                cout<<"1/4"<<endl;
                if (diff==seven_eights)
                        cout<<"7/8"<<endl;
                if (diff==five_eights)
                        cout<<"5/8"<<endl;
                if (diff==three_eights)
                        cout<<"3/8"<<endl;
                if (diff==one_eight)
                        cout<<"1/8"<<endl;
                if (diff==one_sixteen)
                        cout<<"1/16"<<endl;
                if (diff==one_third)
                        cout<<"1/3"<<endl;
                if (diff==two_third)
                        cout<<"2/3"<<endl;
                if(diff==two_fifths)
                        cout<<"2/5"<<endl;
                if(diff==one_tenths)
                        cout<<"1/10"<<endl;
                if(diff==nine_tenths)
                        cout<<"9/10"<<endl;
                else
                        cout<<diff<<endl<<endl;
                       
                }



//OUTPUT::__________________________________________

                1/2 + 2/5 = 0.900

            The difference from a whole (1.0) is:

                1.0 - 0.900 = 0.100  <<<<<THIS SHOULD BE 1/10

                  ______________________________________

Do you want to use the program again? (yes or no)
        >->:

---

end of program
__________________________________________________ __

THANK YOU FOR YOUR HELP

Fixed tags for you
-Govtcheez

the output in both the result and the difference has to be fractional...

Obviously your three_quarter, one_half variables/defines have some meaning for you, but we need to know how you have defined them, show us where these get set. Also, if they are floating point values (float or double data type), then simply comparing result to these values using == might not work due to limits in precision. You may need to do something like this:

Code:

---

if ( (result >= three_quarter - FLT_EPSILON)
      && (result <= three_quarter + FLT_EPSILON) )
    cout<<"3/4"<<endl;

---

Also, a final comment, if you really have these two long if-else if statements in your code, you might want to consider making it into a function that takes an argument. Then you just call the function twice, once for result and once for diff.

then i should use double;

the purpose of the program was to use the if statement, and struct

the output should have the most common fractions like
1/2, 3/4, but not like 1/234 or 2/549.

the program will be inproved as I progress on the class that I am taking.

heres values that i have for the variables

[tag

---------------------------
using namespace std;
struct math

{
float oneFRAC, twoFRAC;
float numTWO, denomTWO;
};



void main()
{
system("color 4B");
string response;
const float seven_eights=.875;
const float five_eights=.625;
const float three_eights=0.375;
const float one_eight=0.125;
const float one_sixteen=0.0625;
const float three_quarter=0.750;
const float one_half=0.500;
const float one_quarter=0.250;
const double two_fifths=0.400;
const double one_tenths=0.100;
const double one_third=0.33333;
const double two_third=0.66666;
const double nine_tenths=0.900;
float Digit_1, Digit_2;
char oper;
float result;
double diff;

do{

math frac; //define the structure object


cout<<"\t\t+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ =+=+="<<endl;
cout<<"\t\tEnter the nominator of the FIRST fraction\n"
"\t\tThen press enter to input the denominator"<<endl;
cout<<"\t\t+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+ =+=+=\n\n"<<endl;


cout<<" ";
cin>>frac.oneFRAC; //input-(fract #1, num)
cout<<"___";
cout<<"\n";
cout<<" ";
cin>>frac.twoFRAC; //input-(fract#1, denom)
system("cls");

cout<<"\n What action do you want to perform?"<<endl;
cout<<">> [ +, -, x, / ] <<"<<endl;
cout<<" :";
cin>>oper;

system("cls");


tag]

thank you all for your help.!