₦airaland Forum

I can't seem to find the bug in this my program


====================================================================
roman_to_dec.h

#include <string>
using namespace std;

int M, D, C, L, X, V, I;

class romanType{
public:
romanType();
void set_roman_type(string);
int get_roman_type()const;
int convert_rom_to_dec();
int get_answer_in_decimal()const;
~romanType();

private:
int answer_in_decimal;
string roman;
};


-----------------------------------------------------------------------------------------------------------------------------
roman_to_dec.cpp

#include <iostream>
#include <string>
#include <cstring>
#include "roman_to_dec.h"

int display_menu();
void switch_stat(int, romanType);

using namespace std;

int input;

romanType::romanType(){

answer_in_decimal = 0;

roman = " ";
}


void romanType::set_roman_type(string x){

for(int i = 0; i < 10; i++ )
x[i] = roman[i];
}

int romanType::convert_rom_to_dec(){

int answer;


int roman1, roman2;

string::size_type i = 0;

while (i < roman.length()){

switch(toupper(roman.at(i))){

case 'M': roman1 = 1000;
break;

case 'D': roman1 = 500;
break;

case 'C': roman1 = 100;
break;

case 'L': roman1 = 50;
break;

case 'X': roman1 = 10;
break;

case 'V': roman1 = 5;
break;

case 'I': roman1 = 1;
break;

default: roman1 = -1;
}

switch(toupper(roman.at(i + 1))){

case 'M': roman2 = 1000;
break;

case 'D': roman2 = 500;
break;

case 'C': roman2 = 100;
break;

case 'L': roman2 = 50;
break;

case 'X': roman2 = 10;
break;

case 'V': roman2 = 5;
break;

case 'I': roman2 = 1;
break;

default: roman2 = -1;
}

if ((roman1 == -1) || (roman2 == -1)){

cout <<"\n\n\tError incorrect input";
return -1;
}

else if (roman1 < roman2){

answer = roman2 - roman1;
i +=2;
}

else if (roman1 >= roman2){

answer += roman[i];
i +=1;
}

}

answer_in_decimal = answer;

return answer;
}


int romanType::get_answer_in_decimal()const{

return answer_in_decimal;
}
romanType::~romanType(){

cout << "calling destructor";
}


int display_menu(){

cout << "\n\t---------------------------------------------------------------------";
cout << "\n\t---------This program converts Roman Numerals to Decimals -----------";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Press 1 to perform a new converstion |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Press 2 to view last result |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Or press 0 to exit |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t---------------------------------------------------------------------\n\n\t";

cin >> input;


while ((input != 0) && (input > 2)){

cout << "error incorrect input\n try again";

cout << "\n\t---------------------------------------------------------------------";
cout << "\n\t---------This program converts Roman Numerals to Decimals -----------";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Press 1 to perform a new converstion |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Press 2 to view last result |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t| Or press 0 to exit |";
cout << "\n\t| |";
cout << "\n\t| |";
cout << "\n\t---------------------------------------------------------------------\n\n\t";

cin >> input;

}

return input;

}



void switch_stat(int input, romanType roman_type){

string input_roman;

switch(input){

case 0: cout <<"exiting the program\n\n";
break;

case 1: cout << "input the numbers in roman figures:\t";
cin >> input_roman;
roman_type.set_roman_type(input_roman);
roman_type.convert_rom_to_dec();
cout << "\n\n\t" << input_roman << " = " << roman_type.get_answer_in_decimal()<< "in decimal";
cout << endl;
break;

case 2: cout << "testing case.......it works";
break;

default: cout << "\n\tError 505....Incorrect input!!!";
break;
}

}
--------------------------------------------------------------------------------------------------------------------------------

roman_to_dec_main.cpp

#include <iostream>
#include "roman_to_dec.cpp"



int main(){

romanType roman_type;

int input = display_menu();
switch_stat(input, roman_type);


return 0;
}






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this is the error i get whenever i try to run the program


termincate called after throwing an instance of 'std::out_of_range'
what(): basic_string::at _n (which is 1) >= this->size() (which is 1)

this application has requested the Runtime to terminate it in an unusual way.
Please contact he application's support team for more information.

hmm........your program structure is making it hard for me to scan through. Anyways, i tried to reproduce the error but your code kept giving me multiple errors different from the one you posted here

this is the error i get whenever i try to run the program

Please are you sure you were able to pass the COMPILE stage to the RUN stage ?

codemarshal08:
hmm........your program structure is making it hard for me to scan through. Anyways, i tried to reproduce the error but your code kept giving me multiple errors different from the one you posted here

Please are you sure you were able to pass the COMPILE stage to the RUN stage ?

.yes it compiled successfully

I glanced over your code and can see a bug with the second switch statement.

You are testing for roman.at(i + 1) under the premise that i < roman.size().... That's wrong cause when you reach the last element, i will go overboard. If you are ever testing i + x, then your condition should be i - x....
What i am saying is...

Your while loop should be

.....
while (i < roman.length() - 1){
.....

WhiZTiM:
I glanced over your code and can see a bug with the second switch statement.

You are testing for roman.at(i + 1) under the premise that i < roman.size().... That's wrong cause when you reach the last element, i will go overboard. If you are ever testing i + x, then your condition should be i - x....
What i am saying is...

Your while loop should be

.....
while (i < roman.length() - 1){

.....

Please can i get help with this:https://www.nairaland.com/2685865/need-assignment-java-programming#39282992

codemarshal08:
hmm........your program structure is making it hard for me to scan through. Anyways, i tried to reproduce the error but your code kept giving me multiple errors different from the one you posted here

Please are you sure you were able to pass the COMPILE stage to the RUN stage ?

Please i need help:https://www.nairaland.com/2685865/need-assignment-java-programming#39282992

WhiZTiM:
I glanced over your code and can see a bug with the second switch statement.

You are testing for roman.at(i + 1) under the premise that i < roman.size().... That's wrong cause when you reach the last element, i will go overboard. If you are ever testing i + x, then your condition should be i - x....
What i am saying is...

Your while loop should be

.....
while (i < roman.length() - 1){
.....

Thanks.... I also found few bugs out on my own too. the program now runs smoothly

Does anyone knows how to use the Oracle Virtual Machine?