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Segmentation Fault

Regalith (1)
I'm currently trying to create a simple program that does basic arithmetic functions on fractions stored in a class called Rational. The +,-,*,/,==,<,>,>=,<= and = operators are already overloaded. The only issue i have is when running this program with a test file such as:

1/2 3/4 +
1/3 1/4 * 1 +
1/5 4/5

The program segfaults after computing and outputting the first line. Any idea why this might happen? Here's the Code:

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#include "Rational.hpp"
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>

using namespace std;

int main(int argc, char *argv[])
{
	int count = 0;
	while(argv[count] != 0)
	{
		count++;

		ifstream infile(argv[count]);
		char line[256];

		while(infile)
		{
			infile.getline(line,256);
			cout << "YOPP";
	
			char *token = strtok(line," ");

			while(token != NULL) {
				string token2(token);
				int found = token2.find('/');
	
				long int x, y;
				stringstream(token2.substr(0,found)) >> x;
	
				if(found !=-1) {
					found++;
					stringstream(token2.substr(found)) >> y;
				}
				else
					y=1;
	
				Rational rat1 (x,y);
				
				cout << rat1 << " ";	
	
				bool done = false;
				
				token = strtok(NULL," ");
	
				while(token != NULL || done) {
					token2 = string (token);
					found = token2.find('/');
	
					stringstream(token2.substr(0,found)) >> x;
	
					if(found !=-1) {
						found++;
						stringstream(token2.substr(found)) >> y;
					}
					else
						y=1;
	
					Rational rat2 (x,y);
	
					cout << rat2 << " ";
	
					bool equality;
	
					token = strtok(NULL," ");
					
					cout << token << " ";
	
					if(strcmp(token,"+") == 0) {
						rat1 = rat1 + rat2;
					}
					else if(strcmp(token,"-") == 0) {
						rat1 = rat1 - rat2;
					}
					else if(strcmp(token,"*") == 0) {
						rat1 = rat1 * rat2;
					}
					else if(strcmp(token,"/") == 0) {
						rat1 = rat1 / rat2;
					}
					else if(strcmp(token,"<") == 0) {
						equality = rat1 < rat2;
						if(equality) {
							cout << ": true\n";
						}
						else {
							cout << ": false\n";
						}
						done = true;
					}
					else if(strcmp(token,">") == 0) {
						equality = rat1 > rat2;
						if(equality) {
							cout << ": true\n";
						}
						else {
							cout << ": false\n";
						}
						done = true;
					}
					else if(strcmp(token,"<=") == 0) {
						equality = rat1 <= rat2;
						if(equality) {
							cout << ": true\n";
						}
						else {
							cout << ": false\n";
						}
						done = true;
					}
					else if(strcmp(token,">=") == 0) {
						equality = rat1 >= rat2;
						if(equality) {
							cout << ": true\n";
						}
						else {
							cout << ": false\n";
						}
						done = true;
					}
					else if(strcmp(token,"==") == 0) {
						equality = rat1 == rat2;
						if(equality) {
							cout << ": true\n";
						}
						else {
							cout << ": false\n";
						}
						done = true;
					}
					else
						cout << "Error reading line\n";
	
					token = strtok(NULL," ");
				}
				if (!done) {
					cout << ": " << rat1 << " (double " << rat1.toDouble() << ")\n";
				}
				
				cout << "YOPP2 \n";
				
			}
		}
		//infile.close();
	}
	return 0;
}


Thanks
coder777 (8444)
line 12 is supposed look like this:
for(int count = 1; count < argc; ++count)
don't rely on a null pointer

line 17 is supposed look like this:
char line[256 +1]; // +1 due to the additional '\0'!

Don't use strtok(). Use stringstream instead:
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		while(infile)
		{
			string line;
			getline(infile, line);
			cout << "YOPP";
	
			stringstream is(line);

			while(is >> token2) {
				int found = token2.find('/');
You might call strtok() too often
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