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cristina999 (21)
Hey guys so I wrote my code for an assignment and it compiles, for the most part everything works except it will not calculate percentages correctly

The output is supposed to look like this:
Enter problems per set: 3


Set #3
----------
What is the maximum number for this set? 20
0 * 18 = 0
correct
15 * 4 = 398
incorrect
8 * 17 = 873
incorrect

Set#1: You got 2 correct out of 3 for 67%
Set#2: You got 2 correct out of 3 for 67%
Set#3: You got 1 correct out of 3 for 33%
Overall you got 5 correct out of 9 for 56%

However mine will not calculate the percentage correctly and instead outputs this:
2 + 6 = 8
correct
10 + 9 = 19
correct

Set #2
----------
What is the maximum number for this set? 2
2 - 2 = 12
incorrect
2 - 2 = 0
correct

Set #3
----------
What is the maximum number for this set? 4
3 * 2 = 6
correct
2 * 3 = 1
incorrect


Set#1: You got 2 out of 2 for 100%
Set#2: You got 1 out of 2 for 0%
Set#3: You got 1 out of 2 for 0%
Overall you got 4 correct out of 6 for 0%

Process returned 0 (0x0) execution time : 23.097 s
Press any key to continue.

Not sure how I can fix this please leave any suggestions thanks in advance



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  //********************************
// This program will ask the user to answer a series of
//arithmetic questions and will report on how the user performs.
#include <iostream>
#include <ctime> // Will be used by the srand function for time
#include <cstdlib> // will allow for random numbers to be generated.
#include <iomanip>
using namespace std;


void getProbsPerSet(int& numProbs);
// The following functions will have inputs
void doOneSet( char problemType,int numProbs,int& correctCount);// Prototype
void getMaxNum(int &maxNum); // Will need inputs
void printHeader(char problemType);
void doOneProblem(char problemType, int& MaxNum, int & correctCount);
void generateOperands(int& firstNum, int& secondNum, int maxNum);
void calcCorrectAnsw(char problemType, int firstNumber, int secondNum, int& answer);
void checkAnswer (int correctAnsw,int answer, int&correctCount);
void printReport(int probsPerSet, int set1Correct, int set2Correct, int set3Correct);


int main()
{
int probsPerSet;
int set1Correct,set2Correct, set3Correct;
srand(time(0));
getProbsPerSet(probsPerSet);
doOneSet('+', probsPerSet, set1Correct);
doOneSet('-', probsPerSet, set2Correct);
doOneSet('*', probsPerSet, set3Correct);
printReport(probsPerSet,set1Correct, set2Correct, set3Correct);   //a report is generated for the user
                                                                       //telling them how they did
}




void getProbsPerSet(int& numProbs)
//Pre: numProbs is assigned
//Post: numProbs is received from the user and passed to the calling function
{
   cout << "Enter problems per set: ";
   cin >> numProbs;
}



void doOneSet( char problemType,int numProbs,int& correctCount)
//Pre: problemType,numProbs and correctCount are assigned
//Post: output one set of problems
{

   int maxNum;
   correctCount=0;
   printHeader(problemType);
   getMaxNum(maxNum);

   for (int i = 1; i <= numProbs; i++)
   {
       doOneProblem(problemType, maxNum, correctCount);
   }

}



//******************************************************************
// Function void printerHead definition 
//prints out the header at the top of each set denoting the number
//******************************************************************
void printHeader(char problemType)
//Pre: problemType is assigned
//Post: the header is then printed
{
   int setNumber;

   if (problemType == '+')
       setNumber = 1;
   if (problemType == '-')
       setNumber = 2;
   if (problemType == '*')
       setNumber = 3;

   cout << endl << "Set #" << setNumber << endl << "----------" << endl;
}

//*************************************************************************************************
// Function void getMaxNum
// This function allows the user to enter the highest number that may b used in one of the problems
//*************************************************************************************************
void getMaxNum(int &maxNum)
{
   cout << "What is the maximum number for this set? ";
   cin >> maxNum;
}
//************************************************************************
// Function doOneProblem definition 
//creates a single problem with two random numbers and the desired operand,
//collects the user's answer, checks it and passes the number that they
//got correct up to the main function
//************************************************************************
void doOneProblem(char problemType, int& MaxNum, int & correctCount) // delivers the amount of correct problems answer to the main function
{
   int firstNum,secondNum;
   int answer;
   int correctAnswer;
   generateOperands(firstNum, secondNum, MaxNum);
   cout << firstNum << " " << problemType << " " << secondNum << " = ";
   cin >> answer;
   calcCorrectAnsw( problemType,firstNum, secondNum, correctAnswer);
   checkAnswer(answer, correctAnswer, correctCount);
}

//prints out the problem for the user to solve
void generateOperands(int& firstNum, int& secondNum, int maxNum)
{
   firstNum= rand() % maxNum + 1;
   secondNum = rand() % maxNum + 1;
}

//*************************************************************
//Function void calcCorrectAnsw definition
//calculates what the correct answer for the problem should be
//*************************************************************
void calcCorrectAnsw(char problemType, int firstNumber, int secondNum, int& answer)

{
   if (problemType == '+')
       answer = firstNumber + secondNum;
   if (problemType == '-')
       answer = firstNumber - secondNum;
   if (problemType == '*')
       answer = firstNumber * secondNum;
}
//****************************************************************************
//Function void checkAnswer definition
// :checks the user's answer 
// :prints out feedback and increases the count of correct answers for the
// report generated for the user.
//*****************************************************************************
void checkAnswer (int correctAnsw, int answer, int &correctCount) // This function Prototype checks the user's answers
//Pre: validates user answer
//Post: outputs whether or not the user entered the correct answer
{
   if (answer == correctAnsw) // switch statement used to determine the output
                             // " correct" or "incorrect" when he user inputs their answer.
   {
       cout << "correct" << endl;
       correctCount++;
   }
   else
       cout << "incorrect" << endl;
}
//***************************************************************************************************************************************************************
//Pre: Determines how many answers the user input correctly prints out a report telling the user how many problems they got correct out of the total for each set
// Post:and the percentage correct that that equals, and also a total and percentage for all the problems
//****************************************************************************************************************************************************************
void printReport(int probsPerSet, int set1Correct, int m set2Correct, int set3Correct) // Prints a report containing percentages.
//Pre: Analyzes user answers
//Post: outputs a percentage per set and an overall
{
   int totalCorrect = set1Correct + set2Correct + set3Correct;
   int total = probsPerSet * 3.0; // Assumes three sets of problems are done 
                                 // multiplies the number problems chosen by the user by *3

   cout.precision(0);
   cout.setf(ios::fixed);

   cout << endl << endl;
   cout << "Set#1: You got " << set1Correct << " out of " << probsPerSet << " for "
       << ((set1Correct / probsPerSet) * 100 )<< "%" << endl;

   cout << "Set#2: You got " << set2Correct << " out of " << probsPerSet << " for "
       << ((set2Correct / probsPerSet) * 100 )<< "%" << endl;

   cout << "Set#3: You got " << set3Correct << " out of " << probsPerSet << " for "
       << ((set3Correct / probsPerSet) * 100 )<< "%" << endl;

   cout << "Overall you got " << totalCorrect << " correct out of " << total << " for "
       << ((totalCorrect / total) * 100 )<< "%" << endl;
}
Handy Andy (5051)
Hello cristina999,

I see a couple of problems with:

void printReport(int probsPerSet, int set1Correct, int m set2Correct, int set3Correct) // Prints a report containing percentages.

Either you typed a "m" instead of a space or you are missing a comma and type for "set2Correct".

Then for lines 172, 175, 178 and 181 you are doing integer division when it should be double division. For example set 2 should be 1 / 2 giving you the answer of 0.5 * 100, but what you actually get is 0 * 100 which prints a 0. You could fix that with:

((static_cast<double>(set1Correct)/ probsPerSet) * 100 )

I believe that should work I will test it a bit later,

You may find this useful:
http://www.cplusplus.com/forum/beginner/212677/
as it is the same problem.

Hope that helps,

Andy
cristina999 (21)
Hey mate that did it! Thank you :)
The output now reads:
Enter problems per set: 3

Set #1
----------
What is the maximum number for this set? 100
92 + 68 = 160
correct
17 + 43 = 60
correct
24 + 26 = 8
incorrect

Set #2
----------
What is the maximum number for this set? 90
72 - 70 = 2
correct
74 - 16 = -45
incorrect
81 - 19 = 62
correct

Set #3
----------
What is the maximum number for this set? 20
6 * 20 = 120
correct
3 * 12 = 45
incorrect
14 * 4 = 67
incorrect

Set #1: You got 2 correct out of 3 for 67%.
Set #2: You got 2 correct out of 3 for 66.6667%.
Set #3: You got 1 correct out of 3 for 33%.
Overall you got 5 out of 9 for 56%.

Process returned 0 (0x0) execution time : 238.595 s
Press any key to continue.
































































































Handy Andy (5051)
Hello cristina999,

Glad it worked for you although I do not know why your set 2 has a decimal portion to the answer. It did not do that fr me.

Andy
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