Why is this code giving runtime segmentation fault? [duplicate]

Question

Why is this code giving segmentation fault? I am using code::blocks.

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
     int a[555555];
}

Answer 1

This is what called stack overflow.
Generally stack size are small and you can't allocate memory in such a large amount on stack.
For this purpose programmers allocate it on heap (using dynamic allocation). In C, you can use malloc family function

int *a = malloc(sizeof(int)*55555); // Use free(a) to deallocate

In C++ you can use new operator

int *b = new int[555555];   // Use delete [] to deallocate