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Segmentation fault

tatrantea (5)
Hi,

I know this problem is easy, but I can't figure it out by myself. I'm trying to generate 100 random numbers and then plot a histogram. For some reason, when I'm trying to run it, my Linux terminal only gives me a "Segmentation error" message.

Here is the code: 
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time_t seconds;
time(&seconds);
srand((unsigned int) seconds);
int j, k;
int index = 10;
int random_integer[index];
double number[index];
int bin[j];
for (j=0; j<10; j++)
	{bin[j]=0;}
std::cout.precision(4);
std::cout.width(4);
for(int index=0; index<10; index++) {
	random_integer[index] = (rand()%100) + 1;
	number[index] = random_integer[index] / 1000;
	cout << random_integer << number << endl;}     // generate 100 random numbers
	for (j=0; j<10; j++)                     
	{ if ((random_integer[j] >= 0.1*j) && (random_integer[j] < 0.1*j+0.1) ) {bin[j]++;}
	};                                            // put numbers into bins, by their values
for (j=0; j<10; j++)
{cout << j*0.1 << "-" << 0.1*j+0.09 << ": " << bin[j] <<"\n";

By any chance, do you know how to fix it? Or, in general, how to solve segfaults? Thank you very much in advance!
Last edited on
closed account (9wX36Up4)
please write the in [code]
tatrantea (5)
Sorry about that.

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 srand((unsigned)time(0));
int j, k, index;
int random_integer[index];
double number[index];
int bin[j];
std::cout.precision(4);
std::cout.width(4);
for(int index=0; index<100; index++) {
	random_integer[index] = (rand()%1000) + 1;
	number[index] = random_integer[index] / 1000;
	cout << random_integer << number << endl;     // generate 100 random numbers
	for (j=0; j<100; j++)                     
	{ if ((random_integer[j] >= 0.01*j) && (random_integer[j] < 0.01*j+0.01) ) {bin[j]++;}
	};                                            // put numbers into bins, by their values
for (j=0; j<100; j++)
{cout << j*0.01 << "-" << 0.01*j+0.009 << ": "; 
	for (k=0; k<bin[j]; k++) {cout << "*"; }
	cout << "\n";                                // create a histogram from *s
		
cin.get();}
ne555 (10692)
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int j, k, index;
int random_integer[index];
That shouldn't compile. ¿what is the size of the array?

Also, integer division returns an integer
Last edited on
tatrantea (5)
Thank you, ne555!
I realized I should declare the size of the array, so I declared it as 10; I also fixed the integer division, but I'm still getting a segmentation error message when trying to run the program compiled...
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