Program does not terminate - c++

Question

In the following code, when run using GNU GCC v8.2.0, code does not terminate:
int main(void)
{
/* code */
int myArray[] = {2, 4};
int otherArray[] = {777, 888};
for(int i = 0; i<4; i++)
{
myArray[i] = 0;
cout << "myArray[" << i << "]=";
cout << myArray[i] << endl;
cout << "add: " << &myArray[i] << endl;
}
for(int i = 0; i<2; i++)
{
cout << "otherArray[" << i << "]=";
cout << otherArray[i] << endl;
cout << "add: " << &otherArray[i] << endl;
}
return 0;
}
output:
add:0x28ff24
myarray[2]=0
add:0x28ff28
myarray[0]=0
add:0x28ff20
myarray[1]=0
add:0x28ff24
myarray[2]=0
add:0x28ff28
myarray[0]=0
add:0x28ff20
myarray[1]=0
add:0x28ff24
myarray[2]=0
add:0x28ff28
myarray[0]=0
add:0x28ff20
myarray[1]=0
add:0x28ff24
myarray[2]=0
add:0x28ff28
myarray[0]=0
add:0x28ff20
myarray[1]^C

Answer 1

for(int i = 0; i<4; i++)
Replace the 4 in the 'for loop' by 2 like this:
for(int i = 0; i<2; i++)
Since you're using a static array so it's better to specify the fixed size, but the most important is to be aware when you try to access the array by comparing the index being processed with the size of the array to avoid this behavior.

Answer 2

You are invoking undefined behaviour by writing the indexes 0-3 of the 2 element array myArray.
As this is undefined behaviour there are no guarantees as to what is happening or what will happen if you run the code again in the future. A likely explanation for your observed behaviour is that when you write myArray[2] that is actually overwriting the value of i causing your loop to restart back at 0.
The simple solution is to make myArray larger or change your for loop limit to 2.
To detect this sort of behaviour use std::array instead and call the at function which has bounds checking and will throw an exception when you go outside the bounds of the array. e.g.:
#include <array>
#include <iostream>
int main(void)
{
/* code */
std::array< int, 2 > myArray = { 2, 4 };
std::array< int, 2 > otherArray = { 777, 888 };
for(int i = 0; i<4; i++)
{
myArray.at(i) = 0;
std::cout << "myArray[" << i << "]=";
std::cout << myArray[i] << "\n";
std::cout << "add: " << &myArray.at(i) << "\n";
}
for(int i = 0; i<2; i++)
{
std::cout << "otherArray[" << i << "]=";
std::cout << otherArray.at(i) << "\n";
std::cout << "add: " << &otherArray.at(i) << "\n";
}
return 0;
}
std::array also has the bonus of a size() method which can make your code safer too:
for(int i = 0; i<myArray.size(); i++)
{
myArray.at(i) = 0;
std::cout << "myArray[" << i << "]=";
std::cout << myArray[i] << "\n";
std::cout << "add: " << &myArray.at(i) << "\n";
}